chore(stepfunctions): remove integ dependency (#24653)

Removes a dependency between a unit and integration test by extracting generic code into a separate file. Useful for repo restructure as integ tests are in a separate package.

----

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

Author: MrArnoldPalmer

packages/@aws-cdk/aws-stepfunctions/test/fake-task.ts

@@ -0,0 +1,37 @@
+import * as iam from '@aws-cdk/aws-iam';
+import * as constructs from 'constructs';
+import * as sfn from '../lib';
+
+export interface FakeTaskProps extends sfn.TaskStateBaseProps {
+  parameters?: { [key: string]: string };
+}
+
+/**
+ * Task extending sfn.TaskStateBase to facilitate integ testing setting credentials
+ */
+export class FakeTask extends sfn.TaskStateBase {
+  protected readonly taskMetrics?: sfn.TaskMetricsConfig;
+  protected readonly taskPolicies?: iam.PolicyStatement[];
+  protected readonly parameters?: { [key: string]: string };
+
+  constructor(scope: constructs.Construct, id: string, props: FakeTaskProps = {}) {
+    super(scope, id, props);
+    this.parameters = props.parameters;
+  }
+
+  protected _renderTask(): any {
+    return {
+      Type: 'Task',
+      Resource: 'arn:aws:states:::dynamodb:putItem',
+      Parameters: {
+        TableName: 'my-cool-table',
+        Item: {
+          id: {
+            S: 'my-entry',
+          },
+        },
+        ...this.parameters,
+      },
+    };
+  }
+}

packages/@aws-cdk/aws-stepfunctions/test/integ.state-machine-credentials.ts

@@ -1,43 +1,9 @@
 import * as iam from '@aws-cdk/aws-iam';
 import * as cdk from '@aws-cdk/core';
 import { IntegTest } from '@aws-cdk/integ-tests';
-import * as constructs from 'constructs';
+import { FakeTask } from './fake-task';
 import * as sfn from '../lib';
 
-export interface FakeTaskProps extends sfn.TaskStateBaseProps {
-  parameters?: { [key: string]: string };
-}
-
-/**
- * Task extending sfn.TaskStateBase to facilitate integ testing setting credentials
- */
-export class FakeTask extends sfn.TaskStateBase {
-  protected readonly taskMetrics?: sfn.TaskMetricsConfig;
-  protected readonly taskPolicies?: iam.PolicyStatement[];
-  protected readonly parameters?: { [key: string]: string };
-
-  constructor(scope: constructs.Construct, id: string, props: FakeTaskProps = {}) {
-    super(scope, id, props);
-    this.parameters = props.parameters;
-  }
-
-  protected _renderTask(): any {
-    return {
-      Type: 'Task',
-      Resource: 'arn:aws:states:::dynamodb:putItem',
-      Parameters: {
-        TableName: 'my-cool-table',
-        Item: {
-          id: {
-            S: 'my-entry',
-          },
-        },
-        ...this.parameters,
-      },
-    };
-  }
-}
-
 /*
  * Stack verification steps:
  *

packages/@aws-cdk/aws-stepfunctions/test/state.test.ts

@@ -1,5 +1,5 @@
 import * as cdk from '@aws-cdk/core';
-import { FakeTask } from './integ.state-machine-credentials';
+import { FakeTask } from './fake-task';
 import { renderGraph } from './private/render-util';
 import { JsonPath } from '../lib';