OWNERS: sync repositories OWNERS_ALIASES from k/kubevirt to target repositories

[dhiller]

Since k/kubevirt currently is the source of truth when it comes to OWNERS_ALIASES sig_*_approvers and sig_*_reviewers we should sync other repositories OWNERS_ALIASES files in regular intervals, so as to keep them up to date.

Suggestion:

• create a postsubmit that kicks in after a change in k/kubevirt OWNERS_ALIASES gets merged and sync target aliases to the same state as in the source file

          How should we sync between changes here and in k/k?
          IOW, if someone is added as an approver for a SIG, would he need to also add himself to here in a different PR?
  

Originally posted by @iholder101 in kubevirt/community#360 (comment)

[dhiller]

/kind enhancement
/area automation