chore: add revive and fix lint errors

[bupd]

What this PR does / why we need it

• Enable linter revive
• fix lint issues
• fix antipatterns

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #1915

Please check the following list:

• Does the affected code have corresponding tests, e.g. unit test, E2E test?
• Does this change require a documentation update?
• Does this introduce breaking changes that would require an announcement or bumping the major version?
• Do all new files have an appropriate license header?

[codecov]

Codecov Report

❌ Patch coverage is 90.83333% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.14%. Comparing base (992543e) to head (d48db9e).

Files with missing lines	Patch %	Lines
internal/mock/repository.go	0.00%	9 Missing ⚠️
cmd/oras/internal/display/metadata/discard.go	0.00%	1 Missing ⚠️
internal/contentutil/target.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1925      +/-   ##
==========================================
- Coverage   87.22%   87.14%   -0.08%     
==========================================
  Files         143      143              
  Lines        5540     5539       -1     
==========================================
- Hits         4832     4827       -5     
- Misses        421      425       +4     
  Partials      287      287              

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[TerryHowe]

Looks like those errors should be ignored.

[bupd]

@TerryHowe ready to be merged. Thanks for the heads up.

[TerryHowe]

Looks like a conflict in target_test.go

[FeynmanZhou]

@bupd Can you pls resolve the conflict?

[bupd]

@FeynmanZhou done