Makes dynamic configuration work in production

If a static file is mounted in the Docker image, it will be read at
each page load and sent to the client.

package.json

@@ -36,6 +36,7 @@
 	},
 	"type": "module",
 	"dependencies": {
-		"dotenv": "^16.3.1"
+		"dotenv": "^16.3.1",
+		"js-yaml": "^4.1.0"
 	}
 }