Fix linter problems in gitlab-zoekt-indexer

Background

In gitlab-zoekt-indexer!101 (merged) we've discovered that we have quite a bit of linter failures.

Proposal

As part of this issue we can fix the problems one at a time and remove the exceptions we've added in gitlab-zoekt-indexer!101 (merged) under the skip-files: section.

I'm going to create tasks: 1 task to fix offenses in 1 file