remove coveralls from travis (moved to gradle)

Author: Theosakamg

.travis.yml

@@ -31,9 +31,6 @@ before_install:
 script:
 - cd $HOME_BUILD && docker run -u "$UID" -it --rm -v `pwd`:`pwd` -w `pwd` theosakamg7/ros2java:latest sh -c ". ament_ws/install_isolated/local_setup.sh && cd /home/travis/build/ros2_java_ws && ament test --isolated --only rcljava_utils"
 
-after_success:
-  - coveralls
-
 notifications:
   webhooks:
     urls: