Bump vue from 2.6.10 to 3.0.0 in /frontend

Bumps [vue](https://github.com/vuejs/core) from 2.6.10 to 3.0.0.
- [Release notes](https://github.com/vuejs/core/releases)
- [Changelog](https://github.com/vuejs/core/blob/v3.0.0/CHANGELOG.md)
- [Commits](https://github.com/vuejs/core/commits/v3.0.0)

---
updated-dependencies:
- dependency-name: vue
  dependency-type: direct:production
...

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

Author: dependabot[bot]

frontend/package.json

@@ -22,7 +22,7 @@
     "normalize.css": "7.0.0",
     "nprogress": "0.2.0",
     "path-to-regexp": "2.4.0",
-    "vue": "2.6.10",
+    "vue": "3.0.0",
     "vue-router": "3.0.6",
     "vuex": "3.1.0",
     "xlsx": "^0.18.5"