Added Sonarcloud quality gate badge

Author: RobWin

README.adoc

@@ -3,7 +3,7 @@
 :hardbreaks:
 :icons:
 
-image:https://travis-ci.org/resilience4j/resilience4j.svg?branch=master["Build Status", link="https://travis-ci.org/resilience4j/resilience4j"] image:https://sonarcloud.io/api/project_badges/measure?project=resilience4j_resilience4j&metric=coverage["Coverage Status", link="https://sonarcloud.io/dashboard?id=resilience4j_resilience4j"] image:https://api.bintray.com/packages/resilience4j/Maven/resilience4j/images/download.svg[link="https://bintray.com/resilience4j/Maven/resilience4j/_latestVersion"] image:http://img.shields.io/badge/license-ASF2-blue.svg["Apache License 2", link="http://www.apache.org/licenses/LICENSE-2.0.txt"]
+image:https://travis-ci.org/resilience4j/resilience4j.svg?branch=master["Build Status", link="https://travis-ci.org/resilience4j/resilience4j"] image:https://sonarcloud.io/api/project_badges/measure?project=resilience4j_resilience4j&metric=alert_status["Quality Gate", link="https://sonarcloud.io/dashboard?id=resilience4j_resilience4j"] image:https://sonarcloud.io/api/project_badges/measure?project=resilience4j_resilience4j&metric=coverage["Coverage", link="https://sonarcloud.io/dashboard?id=resilience4j_resilience4j"] image:https://api.bintray.com/packages/resilience4j/Maven/resilience4j/images/download.svg[link="https://bintray.com/resilience4j/Maven/resilience4j/_latestVersion"] image:http://img.shields.io/badge/license-ASF2-blue.svg["Apache License 2", link="http://www.apache.org/licenses/LICENSE-2.0.txt"]
 
 == Introduction