enhance: resource group unittest refactory

[chyezh]

issue: #30647
pr: #32739

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.81%. Comparing base (77f4f0c) to head (16c533c).
Report is 2 commits behind head on 2.4.

Additional details and impacted files

@@            Coverage Diff             @@
##              2.4   #32740      +/-   ##
==========================================
+ Coverage   81.72%   81.81%   +0.08%     
==========================================
  Files         998      998              
  Lines      125433   124292    -1141     
==========================================
- Hits       102510   101684     -826     
+ Misses      19075    18755     -320     
- Partials     3848     3853       +5     

see 155 files with indirect coverage changes

[congqixia]

/lgtm

[sre-ci-robot]

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