chg: [vps] improve ``no-matching-entries`` bug detection

bin/vps

@@ -1117,7 +1117,7 @@ EOF
 container:health:check-fix:no-matching-entries() {
     local container_id="$1"
 
-    out=$(docker exec "$container_id" echo 2>&1)
+    out=$(docker exec -u root "$container_id" echo 2>&1)
     errlvl=$?
     [ "$errlvl" == 0 ] && return 0
     service_name=$(docker ps --filter id="$container_id" --format '{{.Label "com.docker.compose.service"}}')