feat(ec2): add VPC interface endpoints for Cognito Identity

[kawaaaas]

Issue # (if applicable)

None

Reason for this change

Cognito Identity supports interface VPC endpoints, but they are currently missing from the AWS CDK's InterfaceVpcEndpointAwsService.

Description of changes

Add interface VPC endpoints

• COGNITO_IDENTITY
• COGNITO_IDENTITY_FIPS

Describe any new or updated permissions being added

None

Description of how you validated changes

$ aws ec2 describe-vpc-endpoint-services --filters "Name=service-name,Values=*cognito-identity*" --region us-east-1 --query "ServiceNames[]"
[
    "com.amazonaws.us-east-1.cognito-identity",
    "com.amazonaws.us-east-1.cognito-identity-fips"
]

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:

❌ Features must contain a change to a README file.
❌ Features must contain a change to a test file.
❌ Features 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.

[badmintoncryer]

Exemption request. We don't need any tests and documentation about this modification.