sync: fix missing import for -q

Some refactors during review dropped this import when it was reworked,
but it's still needed when using the --quiet setting.

Change-Id: I6d9302ef5a056e52415ea63f35bad592b9dfa75d
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/303942
Reviewed-by: Raman Tenneti <rtenneti@google.com>
Tested-by: Mike Frysinger <vapier@google.com>

repo

@@ -298,7 +298,7 @@ def InitParser(parser, gitc_init=False):
                    help='manifest repository location', metavar='URL')
   group.add_option('-b', '--manifest-branch', metavar='REVISION',
                    help='manifest branch or revision (use HEAD for default)')
-  group.add_option('-m', '--manifest-name',
+  group.add_option('-m', '--manifest-name', default='default.xml',
                    help='initial manifest file', metavar='NAME.xml')
   group.add_option('-g', '--groups', default='default',
                    help='restrict manifest projects to ones with specified '

subcmds/sync.py

@@ -51,7 +51,7 @@ import git_superproject
 import gitc_utils
 from project import Project
 from project import RemoteSpec
-from command import Command, MirrorSafeCommand
+from command import Command, MirrorSafeCommand, WORKER_BATCH_SIZE
 from error import RepoChangedException, GitError, ManifestParseError
 import platform_utils
 from project import SyncBuffer