bin/get-pick-list.sh: fix redirection in sh

"&>" is bash specific.

Fixes: e0dbfc9953 ("bin/get-pick-list.sh: warn when commit lists invalid sha")
Cc: Juan A. Suarez <jasuarez@igalia.com>
Cc: Eric Engestrom <eric.engestrom@intel.com>
Cc: Dylan Baker <dylan@pnwbakers.com>
Cc: Emil Velikov <emil.velikov@collabora.com>
Signed-off-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Juan A. Suarez <jasuarez@igalia.com>

bin/get-pick-list.sh

@@ -44,7 +44,7 @@ is_sha_nomination()
 		# Treat only the current line
 		id=`echo "$fixes" | tail -n $fixes_count | head -n 1 | cut -d : -f 2`
 		fixes_count=$(($fixes_count-1))
-		if ! git show $id &>/dev/null; then
+		if ! git show $id >/dev/null 2>&1; then
 			echo WARNING: Commit $1 lists invalid sha $id
 		fi
 	done