fix: [2.5] fix restore rbac empty meta crash

[shaoting-huang]

cp from master: #39141
related: #38985

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[mergify]

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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 69.55%. Comparing base (95809ca) to head (4b7ca95).
Report is 4 commits behind head on 2.5.

❗ There is a different number of reports uploaded between BASE (95809ca) and HEAD (4b7ca95). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (95809ca)	HEAD (4b7ca95)
	2	1

Additional details and impacted files

@@             Coverage Diff             @@
##              2.5   #39143       +/-   ##
===========================================
- Coverage   81.02%   69.55%   -11.48%     
===========================================
  Files        1389      294     -1095     
  Lines      196343    26460   -169883     
===========================================
- Hits       159091    18403   -140688     
+ Misses      31629     8057    -23572     
+ Partials     5623        0     -5623     

Components	Coverage Δ
Client	∅ <ø> (∅)
Core	69.55% <ø> (+<0.01%)	⬆️
Go	∅ <ø> (∅)

see 1096 files with indirect coverage changes

[shaoting-huang]

rerun ut

[github-actions]

Hello shaoting-huang, you are not in the organization, so you do not have the permission to rerun the workflow, please contact @milvus-io/milvus-maintainers for help.