[chore] Fix integration tests workflow to validate SHAs match

[jefchien]

Description of the issue

The GitHub CLI workflow runs the command based off of a branch. If another commit is merged into main before the workflow runs, then that new commit will be triggered by the build completing.

Description of changes

• Validates that the SHAs match and stops the test if they don't.
• Only run the application_signals E2E test if the build is for the main branch since that workflow only runs against main.
• Runs on RELEASE_NOTES change

License

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Tests

https://github.com/aws/amazon-cloudwatch-agent/actions/runs/10307755948
https://github.com/aws/amazon-cloudwatch-agent/actions/runs/10308001488/job/28534467287

Requirements

Before commit the code, please do the following steps.

1. Run make fmt and make fmt-sh
2. Run make lint