Automatic merge from submit-queue

kubeadm: Start using Tolerations in yaml code again and unit-test

**What this PR does / why we need it**:

- Earlier there was a problem with decoding Tolerations from yaml. Seems to be fixed now.
- Added an unit test to catch such a failure if that regression ever happens again

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

**Special notes for your reviewer**:

Targets v1.8

**Release note**:

```release-note
NONE
```
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