forgot to tweak composer script after changing directory name

composer.json

@@ -14,6 +14,6 @@
 	"php": ">=5.6"
     },
     "scripts": {
-        "serve": ["@php -S localhost:29896 ./test/router.php"]
+        "serve": ["@php -S localhost:29896 ./tests/router.php"]
     }
 }