Added Github Bot

[Mil4n0r]

Checklist

• Build process is done without errors. All tests pass in the /lib directory.
• Self-reviewed the code before submitting.
• Meets accessibility standards.
• Added/updated documentation to /website as needed.
• Added/updated tests as needed.

Description
2 actions have been added:

• One immediately sends a message when any user creates an issue, providing general information about them.

• The other detects when an issue/PR has been inactive for a long time and marks it as stale, then closes it later (15 days until stale + 15 days until closed for issues, while 7 days until stale + 7 days until closed for PRs). It also sends a message giving some information about its status. This process gets executed everyday at 1:00 UTC.

Additional context
We should be careful with the pending old issues that we want to keep track of.
Additionally, it seems that there is a default limit of 30 API calls in actions/stale for each execution, so it may take a few days to update the status for all the remaining issues.

Closes #1778

[kukoc]

I like it. the only thing I would open for discussion is the 15 days of inactivity. If that's a fair threshold for everybody , then I would approve.