golangci-lint: enable and fix thelper linter

[mmorel-35]

Please add a summary of your change

enable and fix thelper linter

Please indicate you've done the following:

• [x] Accepted the DCO. Commits without the DCO will delay acceptance.
• [x] Created a changelog file (make new-changelog) or comment /kind changelog-not-required on this PR.
• [ ] Updated the corresponding documentation in site/content/docs/main.

[mmorel-35]

/kind changelog-not-required

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 59.19%. Comparing base (c6264ff) to head (226a4c1). Report is 2 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #8314 +/- ## ======================================= Coverage 59.19% 59.19% ======================================= Files 367 367 Lines 30849 30849 ======================================= Hits 18262 18262 Misses 11125 11125 Partials 1462 1462 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.