Automatic merge from submit-queue (batch tested with PRs 45382, 45384, 44781, 45333, 45543)

azure: improve user agent string

**What this PR does / why we need it**: the UA string doesn't actually contain "kubernetes" in it

**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**: none 

**Release note**:

```release-note
NONE
```

cc: @brendandburns