io/ioutil is deprecated as of Go 1.16 and officially marked as deprecated as of Go 1.19. The same functionality is now provided by package io or package os, and those implementations should be preferred in new code. It is currently used in:

pkg/roachprod/install/cluster_synced.go

Once those uses are removed, update nogo so that it doesn't exclude the files above from its analysis.

Jira issue: CRDB-22006