Fix golangci-lint warnings

[evankanderson]

Summary

Fix errors like https://github.com/stacklok/minder/actions/runs/10780415122/job/29912980252?pr=4382

Change Type

Mark the type of change your PR introduces:

• Bug fix (resolves an issue without affecting existing features)
• Feature (adds new functionality without breaking changes)
• Breaking change (may impact existing functionalities or require documentation updates)
• Documentation (updates or additions to documentation)
• Refactoring or test improvements (no bug fixes or new functionality)

Testing

Read the errors and fixed them.

Review Checklist:

• Reviewed my own code for quality and clarity.
• Added comments to complex or tricky code sections.
• Updated any affected documentation.
• Included tests that validate the fix or feature.
• Checked that related changes are merged.

[coveralls]

coverage: 53.239% (-0.002%) from 53.241%
when pulling 257e440 on evankanderson:fix-lint-errors
into 44d1523 on stacklok:main.

[jhrozek]

FWIW this was the old linter not recognizing iter as being from the go stdlib..

[jhrozek]

I added the nolint so we unblock main

[evankanderson]

I ran make bootstrap to get the newer version of the linter.

[jhrozek]

slap a nolint on TestEventer so we can merge :-) who cares about cyclomatic complexity on test functions.