Update CI badge

A broken build passing badge gives the wrong impression. This should point to the desired Github Action (ci.yml) and updates the badge according to https://docs.github.com/en/actions/monitoring-and-troubleshooting-workflows/adding-a-workflow-status-badge

README.md

@@ -1,5 +1,5 @@
 [![Join the chat at https://gitter.im/linkedin-Burrow/Lobby](https://badges.gitter.im/linkedin-Burrow/Lobby.svg)](https://gitter.im/linkedin-Burrow/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
-[![Build Status](https://travis-ci.org/linkedin/Burrow.svg)](https://travis-ci.org/linkedin/Burrow)
+[![Build Status](https://github.com/linkedin/Burrow/actions/workflows/ci.yml/badge.svg)]([https://travis-ci.org/linkedin/Burrow](https://github.com/linkedin/Burrow/actions/workflows/ci.yml/badge.svg))
 [![go report card](https://goreportcard.com/badge/github.com/linkedin/Burrow)](https://goreportcard.com/report/github.com/linkedin/Burrow)
 [![Coverage Status](https://coveralls.io/repos/github/linkedin/Burrow/badge.svg?branch=master)](https://coveralls.io/github/linkedin/Burrow?branch=master)
 [![GoDoc](https://godoc.org/github.com/linkedin/Burrow?status.svg)](https://godoc.org/github.com/linkedin/Burrow)