chore(deps): bump vuex from 3.1.1 to 3.1.2 in /frontend (#914)

Bumps [vuex](https://github.com/vuejs/vuex) from 3.1.1 to 3.1.2.
- [Release notes](https://github.com/vuejs/vuex/releases)
- [Commits](https://github.com/vuejs/vuex/compare/v3.1.1...v3.1.2)

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

frontend/package.json

@@ -21,7 +21,7 @@
     "vue": "^2.6.10",
     "vue-i18n": "^8.15.0",
     "vue-router": "^3.1.3",
-    "vuex": "^3.1.1",
+    "vuex": "^3.1.2",
     "vuex-router-sync": "^5.0.0"
   },
   "devDependencies": {