[Actions] Chore: Removes outdated stale github action (#5283)

This github action is no longer used and has been replaced by `workflows/stale.yml`

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## PR-Codex overview
This PR focuses on the removal of the `.github/stale.yml` configuration file, which is used to manage stale issues and pull requests in the repository.

### Detailed summary
- Deleted the file `.github/stale.yml`
- This action may affect how stale issues and pull requests are tracked and managed in the repository.

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Author: gregfromstl