Dev/test cycle when updating a Go file is untenably slow

I made a change to `operator/v1alpha1/types_crdchecker.go` and executed: PROTO_OPTIONAL=1 /usr/bin/time make update-codegen-crds verify-codegen-crds API_GROUP_VERSIONS=operator.openshift.io/v1alpha1 This is after applying a version of https://github.com/openshift/api/pull/2530 which ensures that invocations of codegen only target a single group/version. The output was: ``` 135.50user 301.99system 14:03.37elapsed 51%CPU (0avgtext+0avgdata 469820maxresident)k 12200inputs+195520outputs (22major+17349270minor)pagefaults 0swaps ``` so 14 minutes. That's not quite as bad as reprinting your punch cards and waiting for time on the mainframe, but it's still not conducive to iterating on a problem you're trying to understand. This is a beefy workstation-spec laptop. Please can we either make this *much* faster (a minute or less), or clearly document a more streamlined method of rapidly iterating on a verify failure in a single `api.go`?