Remove unused imports

flake8 reports:

  F401 'name' imported but unused

Change-Id: Id45d6efa87ddf53f2c4a0f0c4136ea361ab1b746
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/254592
Reviewed-by: Mike Frysinger <vapier@google.com>
Tested-by: David Pursehouse <dpursehouse@collab.net>