Add integration test to PR https://github.com/aws/aws-sam-cli/pull/2458, and resolve the dedupe_function_routes issue

[wchengru]

Issue #, if available:
This pr is to add the integration tests to aws#2458
It validate the following cases:

• For swaggers in restApi, the operationId is successfully added to requestContext
• For swaggers in httpApi, the operationId is not in requestContext
• For AWS::ApiGateway::Method, the operationName field is successfully added to requestContext
• For AWS::ApiGatewayV2::Route, the operationName field is NOT added to requestContext

Also, it resolved the dedupe_function_routes.

Why is this change necessary?

How does it address the issue?

What side effects does this change have?

Did you change a dependency in requirements/base.txt?
If so, did you run make update-reproducible-reqs

Checklist:

• Write Design Document (Do I need to write a design document?)
• Write unit tests
• Write/update functional tests
• Write/update integration tests
• make pr passes
• Write documentation

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