server: clone ReplicationModeConfig to avoid data race (#4343)

[ti-chi-bot]

This is an automated cherry-pick of #4343

Signed-off-by: disksing [email protected]

What problem does this PR solve?

close #4325

What is changed and how it works?

clone the config so it will be safe to update.

Check List

• Need to cherry-pick to the release branch

Release note

Fix data race when updating replication mode configuration

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• nolouch

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[codecov]

Codecov Report

Merging #4370 (77cfad4) into release-5.3 (31ad343) will decrease coverage by 0.13%.
The diff coverage is 100.00%.

@@               Coverage Diff               @@
##           release-5.3    #4370      +/-   ##
===============================================
- Coverage        75.03%   74.90%   -0.14%     
===============================================
  Files              264      264              
  Lines            27279    27279              
===============================================
- Hits             20470    20433      -37     
- Misses            5005     5034      +29     
- Partials          1804     1812       +8     

Flag	Coverage Δ
unittests	74.90% <100.00%> (-0.14%)	⬇️

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

Impacted Files	Coverage Δ
server/server.go	71.85% <100.00%> (-0.15%)	⬇️
server/tso/local_allocator.go	64.86% <0.00%> (-13.52%)	⬇️
server/region_syncer/server.go	83.08% <0.00%> (-5.89%)	⬇️
server/tso/allocator_manager.go	64.16% <0.00%> (-4.50%)	⬇️
server/region_syncer/client.go	79.68% <0.00%> (-3.91%)	⬇️
server/tso/tso.go	63.63% <0.00%> (-1.71%)	⬇️
server/grpc_service.go	50.20% <0.00%> (-0.71%)	⬇️
client/client.go	71.44% <0.00%> (-0.58%)	⬇️
server/cluster/cluster.go	82.44% <0.00%> (-0.35%)	⬇️
... and 12 more

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[disksing]

/merge

[ti-chi-bot]

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

/run-all-tests

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: 44530c4