fold-security-update-branches: Fix error on command line

Drop the shift after the main case for arguments as it is bogus, and
triggers an error in case of multiple options like -g -o.

Signed-off-by: Walter Lozano <walter.lozano@collabora.com>

release-scripts/fold-security-update-branches

@@ -246,8 +246,6 @@ case "$1" in
         exit 0
         ;;
 esac
-shift "$(($OPTIND -1))"
-
 
 if [ -z "$RELEASE" ]
 then