Bump @types/node from 20.3.3 to 20.8.10 in /test/util

Bumps [@types/node](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/node) from 20.3.3 to 20.8.10.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/node)

---
updated-dependencies:
- dependency-name: "@types/node"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

test/util/package.json

@@ -20,7 +20,7 @@
     "@types/mdast": "^4.0.0",
     "@types/mocha": "^10.0.1",
     "@types/mock-fs": "^4.13.1",
-    "@types/node": "^20.3.3",
+    "@types/node": "^20.8.10",
     "@types/sinon": "^10.0.16",
     "@types/unist": "^3.0.1",
     "@types/yargs": "^17.0.24",