Automatic merge from submit-queue
Pipe in upgrade image target for kube-proxy migration tests
**What this PR does / why we need it**:
https://k8s-testgrid.appspot.com/sig-network#gci-gce-latest-upgrade-kube-proxy-ds&width=20
and
https://k8s-testgrid.appspot.com/sig-network#gci-gce-latest-downgrade-kube-proxy-ds&width=20
are still failing.
Reproduced it locally and found node image is being default to debian during upgrade (it was gci before upgrade) because we don't pass in `gci` via `--upgrade--target`. And for some reasons (haven't figured out yet), the upgraded node uses debian image with gci startupscripts...
This PR pipes in `--upgrade-target` for kube-proxy migration tests, hopefully in conjunction with https://github.com/kubernetes/test-infra/pull/4447 it will bring the tests back to normal.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #NONE
**Special notes for your reviewer**:
Sorry for bothering again.
/assign @krousey
**Release note**:
```release-note
NONE
```
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