Fix issue 6575

[Lyndon-Li]

Fix issue #6575, flush the repo after delete the snapshot, otherwise, the changes(deleting repo snapshot) cannot be committed to the repo.

[codecov-commenter]

Codecov Report

Merging #6587 (7b2d78e) into main (7135f16) will decrease coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #6587      +/-   ##
==========================================
- Coverage   60.18%   60.15%   -0.03%     
==========================================
  Files         242      242              
  Lines       25636    25640       +4     
==========================================
- Hits        15428    15424       -4     
- Misses       9135     9142       +7     
- Partials     1073     1074       +1     

Files Changed	Coverage Δ
pkg/repository/provider/unified_repo.go	87.56% <100.00%> (+0.13%)	⬆️

... and 1 file with indirect coverage changes