Update dependency serverless to v4

Author: renovate[bot]

package.json

@@ -5,7 +5,7 @@
     "main": "index.js",
     "devDependencies": {
         "@serverless/utils": "6.15.0",
-        "serverless": "<4.0.0",
+        "serverless": "<5.0.0",
         "serverless-offline": "13.9.0",
         "serverless-offline-ssm": "6.2.0",
         "serverless-prune-plugin": "2.1.0",