chore: cherry pick since version X

[lmatz]

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What's changed and what's your intention?

is replacing the old label a good idea? or keep both?

Just checked with owners a few commits that are in 2.1 but not in 2.2 found by @xiangjinwu
most of them are not needed, i.e. specific fixes for 2.1.

#19700
#19934
#20070
#20043
#20269

Checklist

• I have written necessary rustdoc comments.
• I have added necessary unit tests and integration tests.
• I have added test labels as necessary.
• I have added fuzzing tests or opened an issue to track them.
• My PR contains breaking changes.
• My PR changes performance-critical code, so I will run (micro) benchmarks and present the results.
• My PR contains critical fixes that are necessary to be merged into the latest release.

Documentation

• My PR needs documentation updates.

Release note

[cyliu0]

LGTM