Bump merge and @vue/cli in /ui

Removes [merge](https://github.com/yeikos/js.merge). It's no longer used after updating ancestor dependency [@vue/cli](https://github.com/vuejs/vue-cli/tree/HEAD/packages/@vue/cli). These dependencies need to be updated together.


Removes `merge`

Updates `@vue/cli` from 4.5.19 to 5.0.9
- [Release notes](https://github.com/vuejs/vue-cli/releases)
- [Changelog](https://github.com/vuejs/vue-cli/blob/dev/CHANGELOG.md)
- [Commits](https://github.com/vuejs/vue-cli/commits/v5.0.9/packages/@vue/cli)

---
updated-dependencies:
- dependency-name: merge
  dependency-version:
  dependency-type: indirect
- dependency-name: "@vue/cli"
  dependency-version: 5.0.9
  dependency-type: direct:development
...

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

ui/package.json

@@ -81,7 +81,7 @@
   },
   "devDependencies": {
     "@babel/core": "^7.17.5",
-    "@vue/cli": "^4.4.1",
+    "@vue/cli": "^5.0.9",
     "@vue/cli-plugin-babel": "~4.5.0",
     "@vue/cli-plugin-eslint": "~4.5.0",
     "@vue/cli-plugin-router": "~4.5.0",