chore(deps): update dependency eslint to v9

Author: renovate[bot]

Diff for: backend/editor/OT/OTClient/package.json

@@ -11,7 +11,7 @@
     "@types/socket.io": "3.0.2",
     "@typescript-eslint/eslint-plugin": "5.33.1",
     "@typescript-eslint/parser": "5.26.0",
-    "eslint": "8.16.0",
+    "eslint": "9.21.0",
     "eslint-config-standard": "17.0.0",
     "eslint-config-standard-with-typescript": "22.0.0",
     "eslint-plugin-import": "2.26.0",