Bump vue and vue-template-compiler

Bumps [vue](https://github.com/vuejs/vue) and [vue-template-compiler](https://github.com/vuejs/vue). These dependencies needed to be updated together.

Updates `vue` from 2.6.11 to 2.6.12
- [Release notes](https://github.com/vuejs/vue/releases)
- [Commits](vuejs/vue@v2.6.11...v2.6.12)

Updates `vue-template-compiler` from 2.6.11 to 2.6.12
- [Release notes](https://github.com/vuejs/vue/releases)
- [Commits](vuejs/vue@v2.6.11...v2.6.12)

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

Author: dependabot-preview[bot]

package-lock.json

@@ -6,9 +6,9 @@
     "express": "^4.17.1",
     "marked": "^2.0.0",
     "prismjs": "^1.21.0",
-    "vue": "^2.6.11",
+    "vue": "^2.6.12",
     "vue-router": "^3.4.3",
-    "vue-template-compiler": "^2.6.11",
+    "vue-template-compiler": "^2.6.12",
     "vuex": "^3.5.1"
   },
   "devDependencies": {