Create GitHub action for stale pr

[jennijuju]

Checklist

• This is not a new feature or an enhancement to the Filecoin protocol. If it is, please open an FIP issue.
• This is not a new feature request. If it is, please file a feature request instead.
• This is not brainstorming ideas. If you have an idea you'd like to discuss, please open a new discussion on the lotus forum and select the category as Ideas.
• I have a specific, actionable, and well motivated improvement to propose.

Lotus component

Other

Improvement Suggestion

We have many open PRs that maintainer requested changes but the author doesnt repply. So the suggestion here is to:

• lotus dev add a need/author-input label on the pr's that they requested input from the authur
• if there is no response from the authur for 3 days, a stale label will be assigned and will give a 2 days notice before closing
• the stale label should be removed if the pr has new inputs
• the pr should be closed if there is no activity at all for 2 days