Add badges

Author: biow0lf

README.md

@@ -1,4 +1,8 @@
 # Errbit Github Plugin
 
+[![RSpec](https://github.com/errbit/errbit_github_plugin/actions/workflows/rspec.yml/badge.svg)](https://github.com/errbit/errbit_github_plugin/actions/workflows/rspec.yml)
+[![RSpec on JRuby](https://github.com/errbit/errbit_github_plugin/actions/workflows/jruby.yml/badge.svg)](https://github.com/errbit/errbit_github_plugin/actions/workflows/jruby.yml)
+[![Ruby Style Guide](https://img.shields.io/badge/code_style-standard-brightgreen.svg)](https://github.com/standardrb/standard)
+
 This plugin provides GitHub issue tracker integration for Errbit and it is the
 only plugin included by default in Errbit.