fix: example/package.json & example/yarn.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-RAMDA-1582370

Author: snyk-bot

example/package.json

@@ -11,6 +11,6 @@
     "serverless-plugin-aws-alerts": "^1.2.4"
   },
   "dependencies": {
-    "serverless": "^1.71.3"
+    "serverless": "^2.0.0"
   }
 }