schedule: add metrcis for region scatter (#3582)

[ti-srebot]

cherry-pick #3582 to release-4.0
You can switch your code base to this Pull Request by using git-extras:

# In pd repo:
git pr https://github.com/tikv/pd/pull/3595

After apply modifications, you can push your change to this PR via:

git push git@github.com:ti-srebot/pd.git pr/3595:release-4.0-b8c3d1445bb7

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Signed-off-by: yisaer disxiaofei@163.com

What problem does this PR solve?

Add metrics in region scatter

What is changed and how it works?

Release note

• No release note

[ti-srebot]

@Yisaer you're already a collaborator in bot's repo.

[Yisaer]

/merge

[ti-chi-bot]

@Yisaer: 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]

@Yisaer: /merge in this pull request requires 2 /lgtm.

In response to this:

/merge

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.

[sonarqubecloud]

SonarCloud Quality Gate failed.

0 Bugs
0 Vulnerabilities
0 Security Hotspots
14 Code Smells

No Coverage information
3.1% Duplication

[Yisaer]

/hold cancel

[Yisaer]

/merge

[ti-chi-bot]

@Yisaer: 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]

@Yisaer: /merge in this pull request requires 2 /lgtm.

In response to this:

/merge

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]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• Yisaer
• lhy1024

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

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Reviewer can indicate their review by writing /lgtm in a comment.
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[Yisaer]

/merge

[ti-chi-bot]

@Yisaer: 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: c94a0a1

[codecov]

Codecov Report

Merging #3595 (c94a0a1) into release-4.0 (f71ab12) will decrease coverage by 0.13%.
The diff coverage is 63.33%.

@@               Coverage Diff               @@
##           release-4.0    #3595      +/-   ##
===============================================
- Coverage        74.75%   74.62%   -0.14%     
===============================================
  Files              211      211              
  Lines            19880    19908      +28     
===============================================
- Hits             14861    14856       -5     
- Misses            3683     3725      +42     
+ Partials          1336     1327       -9     

Flag	Coverage Δ
unittests	74.62% <63.33%> (-0.14%)	⬇️

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

Impacted Files	Coverage Δ
server/schedule/filter/filters.go	85.09% <ø> (ø)
server/schedule/region_scatterer.go	74.75% <60.71%> (-2.53%)	⬇️
server/schedule/metrics.go	100.00% <100.00%> (ø)
server/cluster/coordinator.go	60.42% <0.00%> (-6.96%)	⬇️
server/tso/tso.go	80.43% <0.00%> (-3.63%)	⬇️
server/member/lease.go	91.07% <0.00%> (-3.58%)	⬇️
pkg/etcdutil/etcdutil.go	77.94% <0.00%> (-2.95%)	⬇️
server/kv/etcd_kv.go	78.26% <0.00%> (-1.45%)	⬇️
server/member/leader.go	67.43% <0.00%> (-1.38%)	⬇️
client/client.go	69.54% <0.00%> (-0.51%)	⬇️
... and 8 more

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