pyflakes: Fix remaining "E501 line too long" warnings

We increased the max line length to 100 columns which got rid of
the majority of these warnings, but there were still a few lines
that exceeded 100 columns.

Change-Id: Ib3372868ca2297f83073a14f91c8ae3df9d0d0e6
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/254699
Tested-by: David Pursehouse <dpursehouse@collab.net>
Reviewed-by: Mike Frysinger <vapier@google.com>

main.py

@@ -229,7 +229,8 @@ class _Repo(object):
       if e.name:
         print('error: project group must be enabled for project %s' % e.name, file=sys.stderr)
       else:
-        print('error: project group must be enabled for the project in the current directory', file=sys.stderr)
+        print('error: project group must be enabled for the project in the current directory',
+              file=sys.stderr)
       result = 1
     except SystemExit as e:
       if e.code: