build: update @fortawesome/fontawesome-free-brands requirement to 5.0.12

Updates the requirements on [@fortawesome/fontawesome-free-brands](https://github.com/FortAwesome/Font-Awesome) to permit the latest version.
- [Release notes](https://github.com/FortAwesome/Font-Awesome/releases)
- [Changelog](https://github.com/FortAwesome/Font-Awesome/blob/master/CHANGELOG.md)
- [Commits](https://github.com/FortAwesome/Font-Awesome/commits/5.0.12)

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

package.json

@@ -33,7 +33,7 @@
   },
   "dependencies": {
     "@fortawesome/fontawesome": "1.1.7",
-    "@fortawesome/fontawesome-free-brands": "5.0.11",
+    "@fortawesome/fontawesome-free-brands": "5.0.12",
     "@fortawesome/fontawesome-free-regular": "5.0.12",
     "@fortawesome/fontawesome-free-solid": "5.0.12",
     "@fortawesome/vue-fontawesome": "0.0.22",