Bot to automatically close stale issues and PRs

[Wwwsylvia]

To reduce maintenance costs and keep the repository clean, we propose implementing a bot that automatically closes stale issues and PRs. As a starting point, we can refer to the stale bot configuration used in the ORAS repository. The proposed rules are as follows:

• Issues with no activity for 60 days will be marked as stale and closed after an additional 30 days of inactivity.
• PRs with no activity for 45 days will be marked as stale and closed after an additional 30 days of inactivity.

[FeynmanZhou]

Sounds good to me.

[shizhMSFT]

SGTM