Update util to 0.12.4

Chrome 92 started to disable `SharedArrayBuffer` without cross-origin isolation which can be enabled by sending [the page with special HTTP headers](https://web.dev/cross-origin-isolation-guide/). This change causes Chrome to emit a warning in DevTools console and [developers are confused with the message](vercel#21708). `util` is one of the libraries that uses `SharedArrayBuffer` and is causing the warning to appear in the console.

Luckily, the issue in `util` has been resolved in [v0.12.4] and I would like to propose applying the fixed version to this library.

For fixing vercel#21708

packages/next/package.json

@@ -110,7 +110,7 @@
     "timers-browserify": "2.0.12",
     "tty-browserify": "0.0.1",
     "use-subscription": "1.5.1",
-    "util": "0.12.3",
+    "util": "0.12.4",
     "vm-browserify": "1.1.2",
     "watchpack": "2.1.1"
   },