Fix with-supertokens example (#62817)

## What?

There was a dependency missing that would immediately cause issues.

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Closes NEXT-2686

examples/with-supertokens/package.json

@@ -11,7 +11,8 @@
     "react": "^18",
     "react-dom": "^18",
     "supertokens-auth-react": "latest",
-    "supertokens-node": "latest"
+    "supertokens-node": "latest",
+    "supertokens-web-js": "latest"
   },
   "devDependencies": {
     "@types/cookie": "^0.5.2",