Update vue-i18n requirement from 8.6.0 to 8.7.0 (#3889)

Updates the requirements on [vue-i18n](https://github.com/kazupon/vue-i18n) to permit the latest version.
- [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/commits/v8.7.0)

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

package.json

@@ -226,7 +226,7 @@
 		"vue-color": "2.7.0",
 		"vue-content-loading": "1.5.3",
 		"vue-cropperjs": "3.0.0",
-		"vue-i18n": "8.6.0",
+		"vue-i18n": "8.7.0",
 		"vue-js-modal": "1.3.28",
 		"vue-loader": "15.4.2",
 		"vue-marquee-text-component": "1.1.1",