server: refactor the independent service check

[rleungx]

What problem does this PR solve?

Issue Number: ref #8477.

What is changed and how does it work?

This is a part of #8517.

Check List

Tests

• Unit test

Release note

None.

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[codecov]

Codecov Report

Attention: Patch coverage is 74.62687% with 17 lines in your changes missing coverage. Please review.

Project coverage is 69.98%. Comparing base (0402e15) to head (c600920).
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8738      +/-   ##
==========================================
- Coverage   70.10%   69.98%   -0.13%     
==========================================
  Files         517      517              
  Lines       79983    79989       +6     
==========================================
- Hits        56076    55980      -96     
- Misses      20339    20436      +97     
- Partials     3568     3573       +5     

Flag	Coverage Δ
unittests	69.98% <74.62%> (-0.13%)	⬇️

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