Remove CircleCI configuration

Author: hidakatsuya

.circleci/config.yml

@@ -35,10 +35,6 @@ $ cd /your/path/redmine
 $ bundle exec rake redmine:plugins:test NAME=redmine_message_customize RAILS_ENV=test
 ```
 
-## CircleCI test
-
-https://circleci.com/gh/farend/redmine_message_customize
-
 ----
 
 2022/6/08 Transferred ownership of the repository from ishikawa999 to [Far End Technologies Corporation](https://github.com/farend).