fix: if directory was empty, there was a nasty message.

bin/compose

@@ -1671,7 +1671,7 @@ get_docker_compose_single_opts_list() {
 
 clean_cache() {
     local i=0
-    for f in $(ls -t "$CACHEDIR/"*.cache.* | tail -n +500); do
+    for f in $(ls -t "$CACHEDIR/"*.cache.* 2>/dev/null | tail -n +500); do
         ((i++))
         rm -f "$f"
     done