fix: update image reference to "@" in audit log when pushing & deleting images

[zyyw]

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Comprehensive Summary of your change

Issue being fixed

Fixes #20341

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• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 66.37%. Comparing base (b7b8847) to head (c3ab410).
Report is 154 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #20348      +/-   ##
==========================================
- Coverage   67.56%   66.37%   -1.19%     
==========================================
  Files         991     1042      +51     
  Lines      109181   113026    +3845     
  Branches     2719     2827     +108     
==========================================
+ Hits        73768    75021    +1253     
- Misses      31449    33954    +2505     
- Partials     3964     4051      +87     

Flag	Coverage Δ
unittests	66.37% <0.00%> (-1.19%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
src/controller/event/topic.go	6.47% <0.00%> (ø)

... and 565 files with indirect coverage changes

[MinerYang]

lgtm

[chlins]

Lgtm