br: fix flaky test (#52573)

[ti-chi-bot]

This is an automated cherry-pick of #52573

What problem does this PR solve?

Issue Number: close #52547

Problem Summary:
the flaky test TestGetTSWithRetry takes too much time.

What changed and how does it work?

less retry

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

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (release-7.1@853d735). Click here to learn what that means.
The diff coverage is 100.0000%.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-7.1     #52666   +/-   ##
================================================
  Coverage               ?   73.4324%           
================================================
  Files                  ?       1211           
  Lines                  ?     379937           
  Branches               ?          0           
================================================
  Hits                   ?     278997           
  Misses                 ?      83120           
  Partials               ?      17820           

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: 3pointer, Leavrth

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• OWNERS [3pointer,Leavrth]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-04-17 09:39:49.3066065 +0000 UTC m=+417408.417652941: ☑️ agreed by 3pointer.
• 2024-04-17 10:42:07.626353263 +0000 UTC m=+421146.737399713: ☑️ agreed by Leavrth.