fix: use echo to output logs

overlay/usr/local/lib/log.sh

@@ -8,7 +8,7 @@ log() {
     message="$2"
     timestamp=$(date +"%Y-%m-%d %H:%M:%S")
     script_name="$(basename "$0")"
-    printf >&2 "%s [%s] [%s] %s" "${timestamp}" "${level}" "$script_name" "${message}"
+    echo >&2 "${timestamp} [${level}] [$script_name] ${message}"
 }
 
 # Log the given message at INFO level. All logs are written to stderr with a timestamp.