lightning: cherry-pick some PRs (#1458)

[ti-chi-bot]

This is an automated cherry-pick of #1458

What problem does this PR solve?

cherry-pick pingcap/tidb#27769 and pingcap/tidb#30393

also cherry-pick pingcap/tidb#29730 to pass integration test

also partically cherry-pick pingcap/tidb#29062 to fix some unstable integration tests

What is changed and how it works?

Check List

Tests

• Unit test

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation

Release note

• Fix the bug that tidb-lightning can only read at most 1000 files from gcs storage.

[ti-chi-bot]

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[ti-chi-bot]

@ti-chi-bot: This cherry pick PR is for a release branch and has not yet been approved by release team.
Adding the do-not-merge/cherry-pick-not-approved label.

To merge this cherry pick, it must first be approved by the collaborators.

AFTER it has been approved by collaborators, please ping the release team in a comment to request a cherry pick review.

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