Bump vuex from 3.1.1 to 3.1.2

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>

package.json

@@ -59,7 +59,7 @@
     "vue-router": "^3.0.1",
     "vue-server-renderer": "^2.6.11",
     "vue-template-compiler": "^2.6.11",
-    "vuex": "^3.0.1",
+    "vuex": "^3.1.2",
     "vuex-router-sync": "^5.0.0",
     "webpack": "^4.6.0",
     "webpack-cli": "^3.1.2",