pkg: move the election to pkg

[rleungx]

Signed-off-by: Ryan Leung rleungx@gmail.com

What problem does this PR solve?

Issue Number: Ref #5838.

What is changed and how does it work?

This PR move election to pkg which could be used as a common functionality.

Check List

Tests

• Unit test

Release note

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

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• JmPotato
• nolouch

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[codecov]

Codecov Report

Base: 75.56% // Head: 75.61% // Increases project coverage by +0.04% 🎉

Coverage data is based on head (9b0630b) compared to base (54f2a32).
Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5767      +/-   ##
==========================================
+ Coverage   75.56%   75.61%   +0.04%     
==========================================
  Files         329      329              
  Lines       32959    32960       +1     
==========================================
+ Hits        24907    24924      +17     
+ Misses       5905     5891      -14     
+ Partials     2147     2145       -2     

Flag	Coverage Δ
unittests	75.61% <100.00%> (+0.04%)	⬆️

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

Impacted Files	Coverage Δ
pkg/election/leadership.go	77.31% <ø> (ø)
pkg/election/lease.go	84.05% <ø> (ø)
server/encryptionkm/key_manager.go	71.71% <ø> (ø)
server/member/member.go	62.10% <ø> (-2.11%)	⬇️
server/tso/allocator_manager.go	65.00% <ø> (+1.12%)	⬆️
server/tso/global_allocator.go	61.25% <ø> (ø)
server/tso/local_allocator.go	71.62% <ø> (+6.75%)	⬆️
server/tso/tso.go	71.91% <ø> (ø)
server/statistics/hot_peer_cache.go	96.92% <100.00%> (+0.01%)	⬆️
pkg/tempurl/tempurl.go	45.00% <0.00%> (-15.00%)	⬇️
... and 33 more

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[JmPotato]

/merge

[ti-chi-bot]

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/run-all-tests

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[ti-chi-bot]

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

Commit hash: 9b0630b

[binshi-bing]

reviewed