add kruise_manager_is_leader metric

[hatowang]

Ⅰ. Describe what this PR does

add leader metric for kruise_manager.

Ⅱ. Does this pull request fix one issue?

Ⅲ. Describe how to verify it

Ⅳ. Special notes for reviews

[kruise-bot]

Welcome @hatowang! It looks like this is your first PR to openkruise/kruise 🎉

[codecov-commenter]

Codecov Report

Merging #917 (4c5fad6) into master (7722528) will decrease coverage by 0.17%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #917      +/-   ##
==========================================
- Coverage   49.37%   49.20%   -0.18%     
==========================================
  Files         119      119              
  Lines       11102    11102              
==========================================
- Hits         5482     5463      -19     
- Misses       4786     4799      +13     
- Partials      834      840       +6     

Flag	Coverage Δ
unittests	49.20% <ø> (-0.18%)	⬇️

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

Impacted Files	Coverage Δ
...roller/uniteddeployment/uniteddeployment_update.go	74.15% <0.00%> (-6.75%)	⬇️
...teddeployment/uniteddeployment_controller_utils.go	63.63% <0.00%> (-4.55%)	⬇️
pkg/controller/cloneset/cloneset_controller.go	50.57% <0.00%> (-2.29%)	⬇️
pkg/controller/uniteddeployment/revision.go	66.41% <0.00%> (-1.53%)	⬇️
...er/uniteddeployment/uniteddeployment_controller.go	70.44% <0.00%> (-1.48%)	⬇️

---

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[FillZpp]

@hatowang Thanks. It seems the user name and email of your commit are not your github config (may be some private git config) and you did not signoff yourself.

Please first git config user.name "YOUR_GITHUB_NAME" and git config user.email "YOUR_GITHUB_EMAIL" in your local kruise repo. Then git commit -s --amend and force push again.

[hatowang]

@hatowang Thanks. It seems the user name and email of your commit are not your github config (may be some private git config) and you did not signoff yourself.

Please first git config user.name "YOUR_GITHUB_NAME" and git config user.email "YOUR_GITHUB_EMAIL" in your local kruise repo. Then git commit -s --amend and force push again.

ok

[FillZpp]

/lgtm

[kruise-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: FillZpp

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