scheduler: add metrics when there is potential reverse

[lhy1024]

What problem does this PR solve?

Issue Number: Close #5570

What is changed and how does it work?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

Release note

None.

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[codecov]

Codecov Report

Attention: Patch coverage is 96.22642% with 2 lines in your changes missing coverage. Please review.

Project coverage is 69.97%. Comparing base (0402e15) to head (853fc4a).
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8741      +/-   ##
==========================================
- Coverage   70.10%   69.97%   -0.14%     
==========================================
  Files         517      517              
  Lines       79983    79987       +4     
==========================================
- Hits        56076    55969     -107     
- Misses      20339    20453     +114     
+ Partials     3568     3565       -3     

Flag	Coverage Δ
unittests	69.97% <96.22%> (-0.14%)	⬇️

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