GitHub Action for Automating Inactive Issue Cleaning

[haydenbspence]

This adds adds a workflow that implements closing inactive issues.

• An action will run every day at 5:00am UTC, it can also be manually ran as needed.
• If an issue has had no activity in 90-days, it will add the tag 'stale' and and comment to notify of the status by commenting on the issue.
• If an issue that has been marked stale is inactive for an additional 90-days, it will close then the issue.

For this to work, the GitHub Repository Secret STALE_PAT must be set to a Personal Access Token (PAT) that allows the workflow to authenticate and perform API calls to GitHub.