📝 docs: add circle ci badge

Author: kazupon

README.md

@@ -1,5 +1,7 @@
 # :globe_with_meridians: vue-i18n-locale-message
 
+[![CircleCI](https://circleci.com/gh/kazupon/vue-i18n-locale-message.svg?style=svg)](https://circleci.com/gh/kazupon/vue-i18n-locale-message)
+
 i18n locale messages management tool / library for vue-i18n
 
 <a href="https://www.patreon.com/kazupon" target="_blank">