fix: [2.5] expand privilege group when list policy in rootcoord

[shaoting-huang]

cherry-pick from: #38758
related: #38757

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.04%. Comparing base (d47372e) to head (d65c25b).
Report is 2 commits behind head on 2.5.

Additional details and impacted files

@@            Coverage Diff             @@
##              2.5   #38760      +/-   ##
==========================================
- Coverage   81.05%   81.04%   -0.01%     
==========================================
  Files        1381     1381              
  Lines      195158   195185      +27     
==========================================
+ Hits       158186   158196      +10     
- Misses      31391    31423      +32     
+ Partials     5581     5566      -15     

Components	Coverage Δ
Client	78.26% <ø> (ø)
Core	69.34% <ø> (ø)
Go	83.03% <100.00%> (-0.01%)	⬇️

Files with missing lines	Coverage Δ
internal/metastore/catalog.go	100.00% <ø> (ø)
internal/metastore/kv/rootcoord/kv_catalog.go	80.81% <100.00%> (+0.10%)	⬆️
internal/rootcoord/meta_table.go	83.30% <100.00%> (ø)
internal/rootcoord/root_coord.go	88.09% <100.00%> (+0.34%)	⬆️

... and 26 files with indirect coverage changes

[mergify]

@shaoting-huang go-sdk check failed, comment rerun go-sdk can trigger the job again.

[shaoting-huang]

rerun go-sdk

[tedxu]

/lgtm
/approve

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [tedxu]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment