Update Jenkins build status badge

Signed-off-by: Stefan Scherer <[email protected]>

README.md

@@ -56,7 +56,7 @@ Installation and documentation
 Contributing
 ------------
 
-[![Build Status](https://jenkins.dockerproject.org/buildStatus/icon?job=docker/compose/master)](https://jenkins.dockerproject.org/job/docker/job/compose/job/master/)
+[![Build Status](https://ci-next.docker.com/public/buildStatus/icon?job=compose/master)](https://ci-next.docker.com/public/job/compose/job/master/)
 
 Want to help build Compose? Check out our [contributing documentation](https://github.com/docker/compose/blob/master/CONTRIBUTING.md).