Add lint-go-gopls

[silverwind]

Uses gopls check <files> as a linter. Tested locally and brings up 149 errors currently for me. I don't think I want to fix them in this PR, but I would like at least to get this analysis running on CI.

List of errors:

modules/indexer/code/indexer.go:181:11: impossible condition: nil != nil
routers/private/hook_post_receive.go:120:15: tautological condition: nil == nil
services/auth/source/oauth2/providers.go:185:9: tautological condition: nil == nil
services/convert/issue.go:216:11: tautological condition: non-nil != nil
tests/integration/git_test.go:332:9: impossible condition: nil != nil
services/migrations/migrate.go:179:24-43: unused parameter: ctx
services/repository/transfer.go:288:48-69: unused parameter: doer
tests/integration/api_repo_tags_test.go:75:41-61: unused parameter: session
tests/integration/git_test.go:696:64-74: unused parameter: baseBranch
tests/integration/gpg_git_test.go:265:27-39: unused parameter: t
tests/integration/gpg_git_test.go:284:23-29: unused parameter: tmpDir
tests/integration/gpg_git_test.go:284:31-35: unused parameter: name
tests/integration/gpg_git_test.go:284:37-42: unused parameter: email

[silverwind]

The gopls check command currently does not set a proper exit code when there are errors, so we would likely have to analyze the output.

[silverwind]

Lint script added which performs error detection and error counting. It should now fail the CI like this and also be much less verbose with module downloads which it apparently does:

/Users/silverwind/git/gitea/modules/git/commit_info_nogogit.go:100:35-54: unused parameter: ctx [windows,amd64]
/Users/silverwind/git/gitea/modules/git/commit_info_nogogit.go:100:35-54: unused parameter: ctx
Found 149 'gopls check' errors
make: *** [Makefile:432: lint-go-gopls] Error 1

[silverwind]

Output and failure detection looks good now. I will add || true so we can merge it without fixing the errors.

[silverwind]

This causes a number of annotations to show up on PRs that we should fix first before merging, otherwise it would be annoying having those show up on every PR.

[silverwind]

Will post an update later on the outstanding issues. I think we should only merge this after all issues have been fixed.

[silverwind]

49 errors left, #30735 will fix a few.

[silverwind]

It seems gopls has no support for //nolint currently, so we need to get more creative for technical debt like this one:

gitea/modules/graceful/manager_windows.go

Lines 44 to 45 in a21ca9b

	//lint:ignore SA1019 We use IsAnInteractiveSession because IsWindowsService has a different permissions profile
	isAnInteractiveSession, err := svc.IsAnInteractiveSession() //nolint:staticcheck

[silverwind]

It seems all deprecations that are warned here already have //nolint comments, so I'll just ignore any error with "is deprecated". Some of these should defintely be looked at though.