chore(probot-stale): add probot-stale configuration

[JLHwung]

Resolve #2637.

Thank you for creating a pull request to contribute to Hexo code! Before you open the request please review the following guidelines and tips to help it be more easily integrated:

• [-] Add test cases for the changes.
• [-] Passed the CI test.

Need Owner Membership of hexo to integrate probot-stale. See https://github.com/probot/stale#usage

[coveralls]

Coverage remained the same at 97.152% when pulling ede480b on chore/probot-stale into 3ee44f4 on master.

[NoahDragon]

LGTM

[JLHwung]

@NoahDragon The probot-stale needs owner membership to integrate, could you give it a try? See https://github.com/probot/stale#usage

[NoahDragon]

@JLHwung Done. Thanks.

[JLHwung]

You are very welcome.

[NoahDragon]

@JLHwung One question about this probot. It seems not working. Is there something I didn't do it correctly?

[JLHwung]

@NoahDragon The configuration should be straightforward and I can't find any complains on the issues of probot-stale. Just a reminder, have you select the Repository access to All Repository on the probot-stale installation page?

[NoahDragon]

I only set it to access the hexo main repo, as the other repos don't have many issues to close.

[JLHwung]

hmm, it should have been working. Maybe we can watch on this issue probot/stale#36.

And notice that the bot seems to checking issues in an infrequent interval, see probot/stale#33.

[NoahDragon]

I see. Thanks for the help. I'll check those issues.