chore: require cli integ test when changing/adding a feature flag. (#34584)

A feature flag has the potential to impact the behavior of all CDK apps, including those defined as part our [CLI integration test package](https://github.com/aws/aws-cdk-cli/tree/main/packages/%40aws-cdk-testing/cli-integ). 

For example: #34556

This PR made it so deploying CDK apps with a lambda function now also requires permissions to create log groups. This is not a breaking change for the CDK, but it did broke in our pipeline because of some permission limitations we impose on it. 

It could have been caught in the test pipeline.

----

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

Author: iliapolo

.github/workflows/request-cli-integ-test.yml

@@ -24,17 +24,7 @@ jobs:
           base_sha: ${{ github.event.pull_request.base.sha }}
           files_yaml: |
             cli:
-              - packages/aws-cdk/bin/**
-              - packages/aws-cdk/lib/**
-              - packages/aws-cdk/test/**
-              - packages/@aws-cdk/cloudformation-diff/lib/**
-              - packages/@aws-cdk/cloudformation-diff/test/**
-              - packages/@aws-cdk-testing/cli-integ/bin/**
-              - packages/@aws-cdk-testing/cli-integ/entrypoints/**
-              - packages/@aws-cdk-testing/cli-integ/lib/**
-              - packages/@aws-cdk-testing/cli-integ/resources/**
-              - packages/@aws-cdk-testing/cli-integ/test/**
-              - packages/@aws-cdk-testing/cli-integ/tests/**
+              - packages/aws-cdk-lib/cx-api/lib/features.ts
   submit-to-test-pipeline:
     environment: test-pipeline
     needs: cli-changes