We've been slightly inconsistent in the license header in files.
Standardize them so we can automate checking.
Change-Id: I3cdf85c9485d33cac2bb05c8080dfada3e5a5e8d
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/500102
Reviewed-by: Gavin Mak <gavinmak@google.com>
Tested-by: Mike Frysinger <vapier@google.com>
Commit-Queue: Mike Frysinger <vapier@google.com>