README.md in mqtt-0.5.0 vs README.md in mqtt-0.6.0

- old
+ new

@@ -1,5 +1,5 @@
-[![Build Status](https://travis-ci.org/njh/ruby-mqtt.svg)](https://travis-ci.org/njh/ruby-mqtt)
+[![Build Status](https://github.com/njh/ruby-mqtt/actions/workflows/build.yml/badge.svg?branch=main)](https://github.com/njh/ruby-mqtt/actions/workflows/build.yml?query=branch%3Amain)
 
 ruby-mqtt
 =========
 
 Pure Ruby gem that implements the [MQTT] protocol, a lightweight protocol for publish/subscribe messaging.