Automatic merge from submit-queue (batch tested with PRs 60166, 61706, 61769). 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>.
Change HAIRPIN_MODE to hairpin-veth as default
**What this PR does / why we need it**:
Change the default HAIRPIN_MODE back to "hairpin-veth".
It was previously "promiscuous-bridge" in order to workaround a kernel bug which deadlocked the machine when hairpin-veth was used. (#27498)
After some thorough manual testing on ubuntu clusters, we feel confident now that the kernel bug is fixed so we should switch back to using hairpin-veth. This will allow us to clean up some ebtables rules that were put in place to make "promiscuous-bridge" work properly.
Once this change goes in, we need to carefully monitor our e2e tests to make sure the bug has not resurfaced.
**Release note**:
```release-note
In a GCE cluster, the default HAIRPIN_MODE is now "hairpin-veth".
```
/cc @freehan @prameshj
/assign @roberthbailey
789a27be9d