fix: examples/list-proposals/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-AXIOS-7361793

examples/list-proposals/package.json

@@ -9,7 +9,7 @@
     "start": "node index.js"
   },
   "dependencies": {
-    "@openzeppelin/defender-admin-client": "1.50.0",
+    "@openzeppelin/defender-admin-client": "1.54.6",
     "dotenv": "^16.3.1"
   }
 }