Clean up utils package

[stefanhaller]

• PR Description

The utils package is a bit of a heterogeneous bag of miscellaneous things at different abstraction levels right now; ideally it should only contain low-level utilities similar to the helpers in utils/slice.go. Further cleanup is possible here, e.g. something like rebase_todo.go shouldn't be in this utils package. This PR doesn't address that, however.

The goal of this PR is just to make it possible to import utils from any other package. Previously it wasn't possible to import it from config, because some of the stuff in utils depended on the config package. So here we move only those things to better places. See the individual commit messages for details.

[codacy-production]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
Report missing for 223978e1	✅ 82.50%

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (223978e)	Report Missing	Report Missing	Report Missing
Head commit (252dda5)	55978	48602	86.82%

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#4538)	40	33	82.50%

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

See your quality gate settings    Change summary preferences

Footnotes

1. Codacy didn't receive coverage data for the commit, or there was an error processing the received data. Check your integration for errors and validate that your coverage setup is correct. ↩

[jesseduffield]

LGTM