Automatic merge from submit-queue (batch tested with PRs 59220, 62927, 63084, 63090, 62284). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

kubeadm: add better test coverage to token.go

**What this PR does / why we need it**:
a PR for adding some more tests in `kubeadm/cmd` for `token.go`.

some areas of the `token.go` like listing, creating and deleting tokens can present challenges.
coverage was increased to around 87%.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:

please, link issue # if you know of such.

**Special notes for your reviewer**:
none

**Release note**:

```release-note
NONE
```