CI does not run RAT check against files under `.github` directory

### Describe the bug

RAT does not check files under hidden directories and therefore does not check any files under the `.github` directory. We currently do have some files without the ASF header:

```
.github/workflows/pr_benchmarks.yml
.github/workflows/pr_comment.yml
```

### To Reproduce

This was discovered when creating the 37.0.0-rc1 release tarball. See https://github.com/apache/arrow-datafusion/issues/9843 for more information.

### Expected behavior

Ideally, we should run the RAT check against the files under `.github`. However, we do not want to run it against hidden directories that are not part of the repository (such as `.git` or `.idea`).

### Additional context

_No response_

Start by inspecting the CI/RAT configuration that determines which repository paths are scanned, using .github/workflows/pr_benchmarks.yml and .github/workflows/pr_comment.yml as fixtures. Reproduce the release-tarball check and verify that files under .github are checked while unrelated hidden directories such as .git and .idea remain excluded.

Written by the indexing model from the issue text.