mgr/dashboard: bump @types/node in /src/pybind/mgr/dashboard/frontend

Bumps [@types/node](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/node) from 12.12.62 to 20.8.0.
- [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-major
...

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

src/pybind/mgr/dashboard/frontend/package.json

@@ -96,7 +96,7 @@
     "@types/cypress-cucumber-preprocessor": "4.0.1",
     "@types/jest": "28.1.3",
     "@types/lodash": "4.14.161",
-    "@types/node": "12.12.62",
+    "@types/node": "20.8.0",
     "@types/swagger-ui": "3.52.0",
     "@typescript-eslint/eslint-plugin": "5.27.1",
     "@typescript-eslint/parser": "5.27.1",