leadership: avoid potential data race (#6636)

[ti-chi-bot]

This is an automated cherry-pick of #6636

What problem does this PR solve?

Issue Number: Close #6635

What is changed and how does it work?

Check List

Tests

• Unit test

Release note

None.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• JmPotato
• rleungx

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[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: -0.17 ⚠️

Comparison is base (1ff614d) 74.99% compared to head (45fa163) 74.82%.

Additional details and impacted files

@@               Coverage Diff               @@
##           release-7.1    #6638      +/-   ##
===============================================
- Coverage        74.99%   74.82%   -0.17%     
===============================================
  Files              408      408              
  Lines            40736    40740       +4     
===============================================
- Hits             30550    30484      -66     
- Misses            7519     7570      +51     
- Partials          2667     2686      +19     

Flag	Coverage Δ
unittests	74.82% <100.00%> (-0.17%)	⬇️

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

Impacted Files	Coverage Δ
pkg/election/leadership.go	86.13% <100.00%> (+1.60%)	⬆️

... and 25 files with indirect coverage changes

☔ View full report in Codecov by Sentry.
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[JmPotato]

/merge

[ti-chi-bot]

@JmPotato: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

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[ti-chi-bot]

@JmPotato: /merge in this pull request requires 2 approval(s).

In response to this:

/merge

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[JmPotato]

/merge

[ti-chi-bot]

@JmPotato: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

You only need to trigger /merge once, and if the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

If you have any questions about the PR merge process, please refer to pr process.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 45fa163