chore(deps): bump vue-i18n from 8.11.2 to 8.12.0 in /frontend (#812)

Bumps [vue-i18n](https://github.com/kazupon/vue-i18n) from 8.11.2 to 8.12.0.
- [Release notes](https://github.com/kazupon/vue-i18n/releases)
- [Changelog](https://github.com/kazupon/vue-i18n/blob/dev/CHANGELOG.md)
- [Commits](https://github.com/kazupon/vue-i18n/compare/v8.11.2...v8.12.0)

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

frontend/package-lock.json

@@ -11562,9 +11562,9 @@
       "dev": true
     },
     "vue-i18n": {
-      "version": "8.11.2",
-      "resolved": "https://registry.npmjs.org/vue-i18n/-/vue-i18n-8.11.2.tgz",
-      "integrity": "sha512-STcpmxqBrG77SyWi7e0Yn/B3DjKR6mSDwYS4F/V7zoi+e/+CPbVb2TaBqFwnrkoDcPmRfjM7nTwsiRQQOGdifw=="
+      "version": "8.12.0",
+      "resolved": "https://registry.npmjs.org/vue-i18n/-/vue-i18n-8.12.0.tgz",
+      "integrity": "sha512-Wh40dvkYZH0CntkhQQEed7nY8P/8xOOHy5Bl9W/WmmmW0oLYIL66XWwOqlcnNbLaL5HGN7XISydYVqXS0Sst9w=="
     },
     "vue-loader": {
       "version": "15.7.0",