enhance: RBAC custom privilege group ut coverage

[shaoting-huang]

issue: #37031

[mergify]

@shaoting-huang

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.13%. Comparing base (70605cf) to head (d8a2cb2).
Report is 2 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #37558       +/-   ##
===========================================
- Coverage   82.42%   68.13%   -14.30%     
===========================================
  Files        1066      290      -776     
  Lines      164588    25395   -139193     
===========================================
- Hits       135665    17302   -118363     
+ Misses      23497     8093    -15404     
+ Partials     5426        0     -5426     

Components	Coverage Δ
Client	∅ <ø> (∅)
Core	68.13% <ø> (∅)
Go	∅ <ø> (∅)

see 1356 files with indirect coverage changes

[congqixia]

/lgtm

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: congqixia, shaoting-huang

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