remove travis badge from readme

README.md

@@ -1,4 +1,4 @@
-# Exponential Backoff [![GoDoc][godoc image]][godoc] [![Build Status][travis image]][travis] [![Coverage Status][coveralls image]][coveralls]
+# Exponential Backoff [![GoDoc][godoc image]][godoc] [![Coverage Status][coveralls image]][coveralls]
 
 This is a Go port of the exponential backoff algorithm from [Google's HTTP Client Library for Java][google-http-java-client].
 
@@ -21,8 +21,6 @@ Use https://pkg.go.dev/github.com/cenkalti/backoff/v4 to view the documentation.
 
 [godoc]: https://pkg.go.dev/github.com/cenkalti/backoff/v4
 [godoc image]: https://godoc.org/github.com/cenkalti/backoff?status.png
-[travis]: https://travis-ci.org/cenkalti/backoff
-[travis image]: https://travis-ci.org/cenkalti/backoff.png?branch=master
 [coveralls]: https://coveralls.io/github/cenkalti/backoff?branch=master
 [coveralls image]: https://coveralls.io/repos/github/cenkalti/backoff/badge.svg?branch=master