Bump hawk and karma in /ui

Bumps [hawk](https://github.com/mozilla/hawk) and [karma](https://github.com/karma-runner/karma). These dependencies needed to be updated together.

Removes `hawk`

Updates `karma` from 2.0.5 to 6.4.0
- [Release notes](https://github.com/karma-runner/karma/releases)
- [Changelog](https://github.com/karma-runner/karma/blob/master/CHANGELOG.md)
- [Commits](karma-runner/karma@v2.0.5...v6.4.0)

---
updated-dependencies:
- dependency-name: hawk
  dependency-type: indirect
- dependency-name: karma
  dependency-type: direct:development
...

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

ui/package.json

@@ -106,7 +106,7 @@
     "http-proxy-middleware": "^0.17.3",
     "ify-loader": "^1.1.0",
     "inject-loader": "^3.0.0",
-    "karma": "^2.0.5",
+    "karma": "^6.4.1",
     "karma-coverage": "^1.1.2",
     "karma-mocha": "^1.3.0",
     "karma-phantomjs-launcher": "^1.0.2",