fix the problem that expired data was not recycled timely due to slow gc speed (#4224)

[ti-chi-bot]

This is an automated cherry-pick of #4224

What problem does this PR solve?

Issue Number: close #4146

Problem Summary: The current gc speed is too slow and the data cannot be reclaimed timely when corresponding region was scheduled to other nodes.

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

fix the problem that expired data was not recycled timely due to slow gc speed

[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.

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[lidezhu]

This change is merged into #3703. Close it.