br: refactor test to use wait checkpoint method (#57612)

[ti-chi-bot]

This is an automated cherry-pick of #57612

What problem does this PR solve?

Issue Number: close #57609

Problem Summary:

What changed and how does it work?

Extract the wait for checkpoint to advance logic in integration test to a method

Check List

Tests

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

  • I checked and no code files have been changed.

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

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[Tristan1900]

/close

[ti-chi-bot]

@Tristan1900: Closed this PR.

In response to this:

/close

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