Automatic merge from submit-queue (batch tested with PRs 39681, 39321, 41018, 40883)
kubeadm: app/util/template.go has unit tests
**What this PR does / why we need it**: There was a TODO tag about adding unit tests, but unit tests have been added and the coverage for that file is ~90%. Tag should be removed.
Adding unit tests is a WIP from #34136
**Special notes for your reviewer**: /cc @luxas @pires
**Release note**:
```release-note
NONE
```
a461eab321