labeler: add region label

[disksing]

Signed-off-by: disksing i@disksing.com

What problem does this PR solve?

Add labeler implementation and support key-range type label rule.

#3839

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

Merging #3968 (f032c6c) into master (7a2ab50) will decrease coverage by 0.02%.
The diff coverage is 79.20%.

@@            Coverage Diff             @@
##           master    #3968      +/-   ##
==========================================
- Coverage   74.70%   74.67%   -0.03%     
==========================================
  Files         250      251       +1     
  Lines       25548    25673     +125     
==========================================
+ Hits        19085    19172      +87     
- Misses       4775     4799      +24     
- Partials     1688     1702      +14     

Flag	Coverage Δ
unittests	74.67% <79.20%> (-0.03%)	⬇️

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

Impacted Files	Coverage Δ
server/schedule/labeler/labeler.go	78.68% <78.68%> (ø)
server/core/storage.go	68.04% <100.00%> (+0.36%)	⬆️
server/region_syncer/server.go	83.08% <0.00%> (-5.89%)	⬇️
server/id/id.go	76.19% <0.00%> (-4.77%)	⬇️
server/tso/tso.go	62.43% <0.00%> (-2.77%)	⬇️
server/server.go	70.51% <0.00%> (-1.52%)	⬇️
pkg/btree/btree.go	85.78% <0.00%> (-0.97%)	⬇️
server/schedule/operator_controller.go	84.75% <0.00%> (-0.80%)	⬇️
server/schedule/operator/step.go	67.44% <0.00%> (-0.67%)	⬇️
server/cluster/cluster.go	82.33% <0.00%> (-0.36%)	⬇️
... and 9 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: 4571e0f

[ti-chi-bot]

@disksing: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

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.

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.