build(deps): bump vue from 2.6.14 to 3.0.0 in /frontend (#36)

Bumps [vue](https://github.com/vuejs/core) from 2.6.14 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-version: 3.0.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

frontend/package-lock.json

@@ -15,7 +15,7 @@
     "markdown-it": "^12.3.2",
     "markdown-it-vue": "^1.1.6",
     "v-click-outside": "^3.1.2",
-    "vue": "^2.6.11",
+    "vue": "^3.0.0",
     "vue-notification": "^1.3.20",
     "vue-router": "^3.5.2",
     "vuex": "^3.6.2"