/kind ci

We're currently trying to support FreeBSD container. (cf. #7727)
To track what should be done, and verify the changes, we need a test environment for FreeBSD and want to run e2e.

There's no official FreeBSD runner but some other 3rd party runners. Can we use those runners?
actions/runner#385

https://github.com/marketplace/actions/freebsd-vm
https://github.com/marketplace/actions/cross-platform-action