fix(scheduler-alpha): remove targetOverrides prop from Schedule (#31799)

### Issue # (if applicable)

N/A

### Reason for this change

The `targetOverrides` prop is adding confusion to the API as it override what is set on the target. A better way to reuse target props would be:
```ts
const targetBaseProps = { input: ...someInput... }

const schedule1 = new Schedule(this, 'Schedule', {
    scheduleExpression: ScheduleExpression.cron({ day: '20' }),
    target: new targets.LambdaInvoke(props.func, {
        ...targetBaseProps,
        // override whatever or not to override
        }),
    }),
});
```

### Description of changes

Removed `targetOverrides` prop and the related tests. Also updated the integ test which was using the prop.

### Description of how you validated changes

Removing a prop so n/a.

### Checklist
- [X] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

----

BREAKING CHANGE: This PR removes the `targetOverrides` prop from the `Schedule` construct.

Author: samson-keung

packages/@aws-cdk/aws-scheduler-alpha/README.md

@@ -285,25 +285,6 @@ const target = new targets.LambdaInvoke(fn, {
 });
 ```
 
-## Overriding Target Properties 
-
-If you wish to reuse the same target in multiple schedules, you can override target properties like `input`, 
-`retryAttempts` and `maxEventAge` when creating a Schedule using the `targetOverrides` parameter:
-
-```ts
-declare const target: targets.LambdaInvoke;
-
-const oneTimeSchedule = new Schedule(this, 'Schedule', {
-    schedule: ScheduleExpression.rate(cdk.Duration.hours(12)),
-    target,
-    targetOverrides: {
-        input: ScheduleTargetInput.fromText('Overriding Target Input'),
-        maxEventAge: Duration.seconds(180),
-        retryAttempts: 5,
-    },
-});
-```
-
 ## Monitoring
 
 You can monitor Amazon EventBridge Scheduler using CloudWatch, which collects raw data 

packages/@aws-cdk/aws-scheduler-alpha/lib/schedule.ts

@@ -4,7 +4,6 @@ import * as kms from 'aws-cdk-lib/aws-kms';
 import { CfnSchedule } from 'aws-cdk-lib/aws-scheduler';
 import { Construct } from 'constructs';
 import { IGroup } from './group';
-import { ScheduleTargetInput } from './input';
 import { ScheduleExpression } from './schedule-expression';
 import { IScheduleTarget } from './target';
 
@@ -26,37 +25,6 @@ export interface ISchedule extends IResource {
    * The arn of the schedule.
    */
   readonly scheduleArn: string;
-
-  /**
-   * The customer managed KMS key that EventBridge Scheduler will use to encrypt and decrypt your data.
-   */
-  readonly key?: kms.IKey;
-}
-
-export interface ScheduleTargetProps {
-  /**
-   * The text, or well-formed JSON, passed to the target.
-   *
-   * If you are configuring a templated Lambda, AWS Step Functions, or Amazon EventBridge target,
-   * the input must be a well-formed JSON. For all other target types, a JSON is not required.
-   *
-   * @default - The target's input is used.
-   */
-  readonly input?: ScheduleTargetInput;
-
-  /**
-   * The maximum amount of time, in seconds, to continue to make retry attempts.
-   *
-   * @default - The target's maximumEventAgeInSeconds is used.
-   */
-  readonly maxEventAge?: Duration;
-
-  /**
-   * The maximum number of retry attempts to make before the request fails.
-   *
-   * @default - The target's maximumRetryAttempts is used.
-   */
-  readonly retryAttempts?: number;
 }
 
 /**
@@ -115,11 +83,6 @@ export interface ScheduleProps {
    */
   readonly target: IScheduleTarget;
 
-  /**
-   * Allows to override target properties when creating a new schedule.
-   */
-  readonly targetOverrides?: ScheduleTargetProps;
-
   /**
    * The name of the schedule.
    *
@@ -342,11 +305,9 @@ export class Schedule extends Resource implements ISchedule {
       target: {
         arn: targetConfig.arn,
         roleArn: targetConfig.role.roleArn,
-        input: props.targetOverrides?.input ?
-          props.targetOverrides?.input?.bind(this) :
-          targetConfig.input?.bind(this),
+        input: targetConfig.input?.bind(this),
         deadLetterConfig: targetConfig.deadLetterConfig,
-        retryPolicy: this.renderRetryPolicy(props.targetOverrides?.maxEventAge?.toSeconds(), props.targetOverrides?.retryAttempts),
+        retryPolicy: this.renderRetryPolicy(),
         ecsParameters: targetConfig.ecsParameters,
         kinesisParameters: targetConfig.kinesisParameters,
         eventBridgeParameters: targetConfig.eventBridgeParameters,
@@ -366,14 +327,9 @@ export class Schedule extends Resource implements ISchedule {
     });
   }
 
-  private renderRetryPolicy(
-    maximumEventAgeInSeconds?: number,
-    maximumRetryAttempts?: number,
-  ): CfnSchedule.RetryPolicyProperty | undefined {
+  private renderRetryPolicy(): CfnSchedule.RetryPolicyProperty | undefined {
     const policy = {
       ...this.retryPolicy,
-      maximumEventAgeInSeconds: maximumEventAgeInSeconds ?? this.retryPolicy?.maximumEventAgeInSeconds,
-      maximumRetryAttempts: maximumRetryAttempts ?? this.retryPolicy?.maximumRetryAttempts,
     };
 
     if (policy.maximumEventAgeInSeconds && (policy.maximumEventAgeInSeconds < 60 || policy.maximumEventAgeInSeconds > 86400)) {

packages/@aws-cdk/aws-scheduler-alpha/test/input.test.ts

@@ -146,24 +146,4 @@ describe('schedule target input', () => {
       },
     });
   });
-
-  test('can override target input', () => {
-    // WHEN
-    const input = ScheduleTargetInput.fromText('Original Input');
-    new Schedule(stack, 'TestSchedule', {
-      schedule: expr,
-      target: new SomeLambdaTarget(func, input),
-      targetOverrides: {
-        input: ScheduleTargetInput.fromText('Overridden Input'),
-      },
-      enabled: false,
-    });
-
-    // THEN
-    Template.fromStack(stack).hasResourceProperties('AWS::Scheduler::Schedule', {
-      Target: {
-        Input: '"Overridden Input"',
-      },
-    });
-  });
 });

packages/@aws-cdk/aws-scheduler-alpha/test/integ.schedule.js.snapshot/aws-cdk-scheduler-schedule.assets.json

@@ -103,16 +103,16 @@
    "Properties": {
     "Name": "TestGroup"
    },
-   "UpdateReplacePolicy": "Retain",
-   "DeletionPolicy": "Retain"
+   "UpdateReplacePolicy": "Delete",
+   "DeletionPolicy": "Delete"
   },
   "UnnamedGroupBE3E48EE": {
    "Type": "AWS::Scheduler::ScheduleGroup",
    "Properties": {
     "Name": "awscdkschedulerschedule-UnnamedGroup-97DBE50D"
    },
-   "UpdateReplacePolicy": "Retain",
-   "DeletionPolicy": "Retain"
+   "UpdateReplacePolicy": "Delete",
+   "DeletionPolicy": "Delete"
   },
   "DefaultSchedule597B0B2C": {
    "Type": "AWS::Scheduler::Schedule",
@@ -236,36 +236,6 @@
     }
    }
   },
-  "TargetOverrideScheduleFF8CB184": {
-   "Type": "AWS::Scheduler::Schedule",
-   "Properties": {
-    "FlexibleTimeWindow": {
-     "Mode": "OFF"
-    },
-    "ScheduleExpression": "rate(12 hours)",
-    "ScheduleExpressionTimezone": "Etc/UTC",
-    "State": "ENABLED",
-    "Target": {
-     "Arn": {
-      "Fn::GetAtt": [
-       "Function76856677",
-       "Arn"
-      ]
-     },
-     "Input": "\"Changed Text\"",
-     "RetryPolicy": {
-      "MaximumEventAgeInSeconds": 360,
-      "MaximumRetryAttempts": 5
-     },
-     "RoleArn": {
-      "Fn::GetAtt": [
-       "Role1ABCC5F0",
-       "Arn"
-      ]
-     }
-    }
-   }
-  },
   "AllSchedulerErrorsAlarmA3246F8C": {
    "Type": "AWS::CloudWatch::Alarm",
    "Properties": {