chore(deps): bump vue-router from 3.0.7 to 3.1.0 in /frontend (#830)

Bumps [vue-router](https://github.com/vuejs/vue-router) from 3.0.7 to 3.1.0.
- [Release notes](https://github.com/vuejs/vue-router/releases)
- [Changelog](https://github.com/vuejs/vue-router/blob/dev/CHANGELOG.md)
- [Commits](https://github.com/vuejs/vue-router/compare/v3.0.7...v3.1.0)

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

frontend/package.json

@@ -20,7 +20,7 @@
     "qrcode.vue": "^1.6.2",
     "vue": "^2.6.10",
     "vue-i18n": "^8.12.0",
-    "vue-router": "^3.0.7",
+    "vue-router": "^3.1.0",
     "vuex": "^3.1.1",
     "vuex-router-sync": "^5.0.0"
   },