refactor: use strings.Builder to improve performance

[rocksload]

Thank you for contributing to Harbor!

Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

strings.Builder has fewer memory allocations and better performance.

More info: golang/go#75190

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.

[wy65701436]

lgtm

[codecov]

Codecov Report

❌ Patch coverage is 73.33333% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 65.86%. Comparing base (c8c11b4) to head (c67332b).
⚠️ Report is 582 commits behind head on main.

Files with missing lines	Patch %	Lines
src/common/api/base.go	0.00%	3 Missing ⚠️
src/pkg/task/dao/execution.go	83.33%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #22453       +/-   ##
===========================================
+ Coverage   45.36%   65.86%   +20.50%     
===========================================
  Files         244     1073      +829     
  Lines       13333   116037   +102704     
  Branches     2719     2931      +212     
===========================================
+ Hits         6049    76433    +70384     
- Misses       6983    35364    +28381     
- Partials      301     4240     +3939     

Flag	Coverage Δ
unittests	65.86% <73.33%> (+20.50%)	⬆️

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

Files with missing lines	Coverage Δ
src/pkg/cached/manager.go	100.00% <100.00%> (ø)
src/pkg/task/dao/execution.go	61.82% <83.33%> (ø)
src/common/api/base.go	10.48% <0.00%> (ø)

... and 984 files with indirect coverage changes

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[bupd]

@wy65701436 @stonezdj

Please add release-note/ before merging the PR

[OrlinVasilev]

@wy65701436 please don't merge PR without proper labels, thank you!