npm: bump @types/node in /vscode-extension-self-contained

Bumps [@types/node](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/node) from 20.19.37 to 20.19.39.
- [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-version: 20.19.39
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

vscode-extension-self-contained/package-lock.json

@@ -55,7 +55,7 @@
         ]
     },
     "devDependencies": {
-        "@types/node": "^20.19.37",
+        "@types/node": "^20.19.39",
         "@types/vscode": "^1.103.0",
         "typescript": "^6.0.2",
         "@vscode/test-electron": "^2.5.2",