t: fix remote-helpers bzr test

So that the committer is reset properly.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Git v1.9.1+fc2

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Merge branch 'fc/master' into tmp/travis-test

* fc/master:
  Git v1.9.1+fc2
  t: fix remote-helpers bzr test

Conflicts:
	t/remote-helpers/bzr.t