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>