build(docs-infra): introduce new process for generating data for the events page (#45588)

This commit introduces a new process for generating data for the AIO
[events page](https://angular.io/events), which streamlines the process
and minimizes duplication and manual work. For more details, see
`aio/scripts/generate-events/README.md`.

PR Close #45588

aio/firebase.json

@@ -253,5 +253,8 @@
         ]
       }
     ]
+  },
+  "database": {
+    "rules": "database.rules.json"
   }
 }