[BUILD] Close stale PRs

## What changes were proposed in this pull request?

This PR proposes to close stale PRs.

What I mean by "stale" here includes that there are some review comments by reviewers but the author looks inactive without any answer to them more than a month.

I left some comments roughly a week ago to ping and the author looks still inactive in these PR below

These below includes some PR suggested to be closed and a PR against another branch which seems obviously inappropriate.

Given the comments in the last three PRs below, they are probably worth being taken over by anyone who is interested in it.

Closes #7963
Closes #8374
Closes #11192
Closes #11374
Closes #11692
Closes #12243
Closes #12583
Closes #12620
Closes #12675
Closes #12697
Closes #12800
Closes #13715
Closes #14266
Closes #15053
Closes #15159
Closes #15209
Closes #15264
Closes #15267
Closes #15871
Closes #15861
Closes #16319
Closes #16324
Closes #16890

Closes #12398
Closes #12933
Closes #14517

## How was this patch tested?

N/A

Author: hyukjinkwon <[email protected]>

Closes #16937 from HyukjinKwon/stale-prs-close.

Author: HyukjinKwon