This simplifies debugging tests and makes the test code more clear and concise.
See https://itnext.io/f-tests-as-a-replacement-for-table-driven-tests-in-go-8814a8b19e9e
While at is, consistently use t.Fatal* instead of t.Error* across tests, since t.Error*
requires more boilerplate code, which can result in additional bugs inside tests.
While t.Error* allows writing logging errors for the same, this doesn't simplify fixing
broken tests most of the time.
This is a follow-up for a9525da8a4
It is better developing vmctl tool in VictoriaMetrics repository, so it could be released
together with the rest of vmutils tools such as vmalert, vmagent, vmbackup, vmrestore and vmauth.
