Update .travis.yml

Author: javadev

.travis.yml

@@ -22,4 +22,5 @@ before_script:
 after_success:
   - codecov
   - python <(curl -s https://raw.githubusercontent.com/TouK/sputnik-ci/master/sputnik-ci.py)
-  - mvn sonar:sonar -Dsonar.projectKey=javadev_underscore-java -Dsonar.organization=javadev-github -Dsonar.host.url=https://sonarcloud.io -Dsonar.login=$SONAR_LOGIN
+  - test $TRAVIS_BRANCH = "master" 
+    mvn sonar:sonar -Dsonar.projectKey=javadev_underscore-java -Dsonar.organization=javadev-github -Dsonar.host.url=https://sonarcloud.io -Dsonar.login=$SONAR_LOGIN