bump golang 1.20.4 on main

[MinerYang]

Thank you for contributing to Harbor!

Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

Please indicate you've done the following:

• 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

Merging #18647 (b90a072) into main (b232c90) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main   #18647   +/-   ##
=======================================
  Coverage   67.39%   67.40%           
=======================================
  Files         984      984           
  Lines      107029   107029           
  Branches     2670     2670           
=======================================
+ Hits        72131    72138    +7     
+ Misses      31015    31009    -6     
+ Partials     3883     3882    -1     

Flag	Coverage Δ
unittests	67.40% <ø> (+<0.01%)	⬆️

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see 7 files with indirect coverage changes

[wy65701436]

LGTM

[chlins]

lgtm