Replaced Travis badge with GitHub actions badge.

README.md

@@ -1,7 +1,7 @@
 WebMock
 =======
 [![Gem Version](https://badge.fury.io/rb/webmock.svg)](http://badge.fury.io/rb/webmock)
-[![Build Status](https://secure.travis-ci.org/bblimke/webmock.svg?branch=master)](http://travis-ci.org/bblimke/webmock)
+[![Build Status](https://github.com/bblimke/webmock/workflows/CI/badge.svg?branch=master)](https://github.com/bblimke/webmock/actions)
 [![Code Climate](https://codeclimate.com/github/bblimke/webmock/badges/gpa.svg)](https://codeclimate.com/github/bblimke/webmock)
 [![Mentioned in Awesome Ruby](https://awesome.re/mentioned-badge.svg)](https://github.com/markets/awesome-ruby)
 [![Inline docs](http://inch-ci.org/github/bblimke/webmock.svg?branch=master)](http://inch-ci.org/github/bblimke/webmock)