fix(ec2): fixing vpc endpoint for eu-isoe-west-1 region

[gudipati]

Issue # (if applicable)

Closes #31690.

Reason for this change

When deploying a stack that creates VPC interface endpoints in the eu-isoe-west-1 region, the generated endpoint
is incorrect. The endpoint uses the default com.amazonaws prefix, but eu-isoe-west-1 region requires the uk.adc-e.cloud prefix.

For example, in eu-isoe-west-1, the ECR Docker endpoint should be uk.adc-e.cloud.eu-isoe-west-1.ecr.dkr

But CDK produces com.amazonaws.eu-isoe-west-1.ecr.dkr

This causes a CloudFormation deployment failure:

    The Vpc Endpoint Service 'com.amazonaws..ecr.dkr' does not exist
    (Service: AmazonEC2; Status Code: 400; Error Code: InvalidServiceName)

This PR updates the prefix for eu-isoe-west-1 region to fix this issue.

Description of changes

Fixed the VPC endpoint prefix for eu-isoe-west-1 region and added unit-tests.
As this is an isolated region, integration tests have not been added.

I was not able to get the complete list of endpoints using aws ec2 describe-vpc-endpoint-services --query 'ServiceNames' as I don't have access to this isolated region but someone with access helped confirm that for these 4 endpoints, they differ from the standard VPCE pattern - (com.amazon.eu-isoe-west-1.*)

uk.adc-e.cloud.eu-isoe-west-1.ebs
uk.adc-e.cloud.eu-isoe-west-1.ecr.api
uk.adc-e.cloud.eu-isoe-west-1.ecr.dkr
uk.adc-e.cloud.eu-isoe-west-1.execute-api

Describe any new or updated permissions being added

N/A

Description of how you validated changes

Validated unit-tests

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

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

[aws-cdk-automation]

The pull request linter fails with the following errors:

❌ Fixes must contain a change to an integration test file and the resulting snapshot.

If you believe this pull request should receive an exemption, please comment and provide a justification. A comment requesting an exemption should contain the text Exemption Request. Additionally, if clarification is needed, add Clarification Request to a comment.

✅ A exemption request has been requested. Please wait for a maintainer's review.

[gudipati]

Exemption Request: As this is an isolated region, integration tests could not be added.