Upgrade to
[v0.19.0](https://github.com/golang/tools/releases/tag/gopls%2Fv0.19.0)
and fix issues. Runs with new `warning` serverity setting. This likely
does less checks than before. Additionally, add `make fix` which runs
modernize. This is also verified on CI.
For the record, here are the issues discoverd when running with `info`
severity, in case we want to fix these:
```
tests/integration/repo_test.go:95:5-14: could use tagged switch on i
tests/integration/api_packages_generic_test.go:149:4-64: could use tagged switch on setting.Packages.Storage.Type
services/webhook/msteams_test.go:33:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:59:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:85:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:111:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:138:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:161:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:187:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:213:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:239:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:266:4-33: could use tagged switch on fact.Name
services/webhook/msteams_test.go:407:4-33: could use tagged switch on fact.Name
tests/integration/api_packages_conan_test.go:350:6-33: could use tagged switch on pf.Name
models/issues/tracked_time_test.go:98:3-18: could use tagged switch on user.ID
tests/integration/api_token_test.go:505:5-43: could use tagged switch on minRequiredLevel
services/gitdiff/gitdiff.go:220:33-46: method "getLineLegacy" is unused
```
---------
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
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
```
