chore: Add unused linter

[mrueg]

What this PR does / why we need it:
This function is unused, so we can drop it.
How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)
None
Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

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[rexagod]

/lgtm

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mrueg, rexagod

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