Bump undici from 7.30.0 to 8.12.2 in /language-server

Bumps [undici](https://github.com/nodejs/undici) from 7.30.0 to 8.12.2.
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v7.30.0...v8.12.2)

---
updated-dependencies:
- dependency-name: undici
  dependency-version: 8.12.2
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

language-server/package-lock.json

@@ -33,6 +33,6 @@
     "vscode-uri": "^3.1.0"
   },
   "devDependencies": {
-    "undici": "^7.23.0"
+    "undici": "^8.12.2"
   }
 }