Automatic merge from submit-queue (batch tested with PRs 59878, 59852). 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>.
Check if netstat or iproute2 is available
**What this PR does / why we need it**:
In https://github.com/kubernetes/kubernetes/pull/59655, I incorrectly assumed that the kubetest image would have net-tools. It doesn't. This checks and uses `ss` from iproute2, *or* `netstat` from net-tools. The kubetest image does appear to have iproute2.
**Release note**:
```release-note
NONE
```
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