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

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (release-7.5@3a7cd61). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-7.5     #52668   +/-   ##
================================================
  Coverage               ?   73.0613%           
================================================
  Files                  ?       1411           
  Lines                  ?     418948           
  Branches               ?          0           
================================================
  Hits                   ?     306089           
  Misses                 ?      93156           
  Partials               ?      19703           

Flag	Coverage Δ
unit	73.0613% <100.0000%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	53.9913% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	54.5895% <0.0000%> (?)

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• br/OWNERS [3pointer,Leavrth]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-05-21 11:50:49.48589804 +0000 UTC m=+2172403.243033614: ☑️ agreed by Leavrth.
• 2024-05-22 03:03:47.309562835 +0000 UTC m=+2227181.066698408: ☑️ agreed by 3pointer.