fix(ec2): fixing vpc endpoint pattern for ecr and ecr docker (#31434)

### Issue # (if applicable)

Closes #.
Internal Tracking ticket P150271569

### Reason for this change

Expected Endpoints for ECR in some isolated regions are as below

gov.ic.hci.csp.us-isof-name.ecr.api,
gov.ic.hci.csp.us-isof-name.ecr.dkr,
uk.adc-e.cloud.eu-isoe-name.ecr.api,
 uk.adc-e.cloud.eu-isoe-name.ecr.dkr,

### Description of changes

As discussed with the ECR Service team, endpoints for the service are being generated in reverse order of the domain suffix.
Since some of the endpoints for other services are still using `com.amazonaws` , added fix only for the partitions and service(ECR) flagged.
 
Cannot do for cn regions on the basis of suffix as both regions have different services under exceptions.

### Description of how you validated changes

Added unit test for validation of endpoint, keeping the region names as `us-isoe-test-1` as the regions are in build stage and could be confidential.

No changes to integration test as the fix is for isolated regions.

### 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*

Author: shikha372

packages/aws-cdk-lib/aws-ec2/lib/vpc-endpoint.ts

@@ -9,6 +9,7 @@ import { ISubnet, IVpc, SubnetSelection } from './vpc';
 import * as iam from '../../aws-iam';
 import * as cxschema from '../../cloud-assembly-schema';
 import { Aws, ContextProvider, IResource, Lazy, Resource, Stack, Token } from '../../core';
+import { PARTITION_MAP } from '../../region-info/build-tools/fact-tables';
 
 /**
  * A VPC endpoint.
@@ -666,8 +667,21 @@ export class InterfaceVpcEndpointAwsService implements IInterfaceVpcEndpointServ
         'redshift', 'redshift-data', 's3', 'sagemaker.api', 'sagemaker.featurestore-runtime', 'sagemaker.runtime', 'securityhub',
         'servicecatalog', 'sms', 'sqs', 'states', 'sts', 'sync-states', 'synthetics', 'transcribe', 'transcribestreaming', 'transfer',
         'workspaces', 'xray'],
+      'us-isof-': ['ecr.api', 'ecr.dkr'],
+      'eu-isoe-': ['ecr.api', 'ecr.dkr'],
     };
-    if (VPC_ENDPOINT_SERVICE_EXCEPTIONS[region]?.includes(name)) {
+
+    const regionPartition = region.split('-').slice(0, 2).join('-');
+    const partitionDetails = PARTITION_MAP[`${regionPartition}-`];
+
+    // Check for specific service name under isolated region prefix
+    const serviceInExceptions = VPC_ENDPOINT_SERVICE_EXCEPTIONS[`${regionPartition}-`]?.includes(name);
+
+    if (serviceInExceptions) {
+      // Endpoints generated in reverse of domain suffix for the services mentioned in map
+      const reverseString = partitionDetails.domainSuffix.split('.').reverse().join('.');
+      return reverseString;
+    } else if (VPC_ENDPOINT_SERVICE_EXCEPTIONS[region]?.includes(name)) {
       return 'cn.com.amazonaws';
     } else {
       return 'com.amazonaws';

packages/aws-cdk-lib/aws-ec2/test/vpc-endpoint.test.ts

@@ -694,6 +694,37 @@ describe('vpc endpoint', () => {
       });
 
     });
+
+    test.each([
+      ['us-isof-test-1', 'gov.ic.hci.csp'],
+      ['eu-isoe-test-1', 'uk.adc-e.cloud'],
+      ['us-east-1', 'com.amazonaws'],
+      ['us-gov-west-1', 'com.amazonaws'],
+      ['cn-northwest-1', 'cn.com.amazonaws'],
+      ['cn-north-1', 'cn.com.amazonaws'],
+    ])('test vpc interface endpoint for ECR can be created correctly in all regions', (region : string, domain: string) => {
+      //GIVEN
+      const stack = new Stack(undefined, 'TestStack', { env: { account: '123456789012', region: region } });
+      const vpc = new Vpc(stack, 'VPC');
+
+      //WHEN
+      vpc.addInterfaceEndpoint('ECR Endpoint', {
+        service: InterfaceVpcEndpointAwsService.ECR,
+      });
+
+      vpc.addInterfaceEndpoint('ECR Docker Endpoint', {
+        service: InterfaceVpcEndpointAwsService.ECR_DOCKER,
+      });
+
+      //THEN
+      Template.fromStack(stack).hasResourceProperties('AWS::EC2::VPCEndpoint', {
+        ServiceName: `${domain}.${region}.ecr.api`,
+      });
+      Template.fromStack(stack).hasResourceProperties('AWS::EC2::VPCEndpoint', {
+        ServiceName: `${domain}.${region}.ecr.dkr`,
+      });
+    });
+
     test.each([
       ['transcribe', InterfaceVpcEndpointAwsService.TRANSCRIBE],
     ])('test vpc interface endpoint with .cn suffix for %s can be created correctly in China regions', (name: string, given: InterfaceVpcEndpointAwsService) => {