sync: fix duplicate word in description

Bug: https://crbug.com/gerrit/12814
Change-Id: Id722eec9a59dded588f13bc605ce2c94b4047265
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/268739
Tested-by: Mike Frysinger <vapier@google.com>
Reviewed-by: David Pursehouse <dpursehouse@digital.ai>

subcmds/sync.py

@@ -138,7 +138,7 @@ if the manifest server specified in the manifest file already includes
 credentials.
 
 By default, all projects will be synced. The --fail-fast option can be used
-to halt syncing as soon as possible when the the first project fails to sync.
+to halt syncing as soon as possible when the first project fails to sync.
 
 The --force-sync option can be used to overwrite existing git
 directories if they have previously been linked to a different