fix: redirect dbus into null

Author: 1ambda

.travis.yml

@@ -120,7 +120,7 @@ before_script:
   - echo "export SPARK_HOME=`pwd`/spark-$SPARK_VER-bin-hadoop$HADOOP_VER" > conf/zeppelin-env.sh
   - echo "export ZEPPELIN_HELIUM_REGISTRY=helium" >> conf/zeppelin-env.sh
   - tail conf/zeppelin-env.sh
-  - if [[ -n $TEST_MODULES ]]; then export CHROME_BIN=chromium-browser; export DISPLAY=:99.0; sh -e /etc/init.d/xvfb start; sleep 3; fi
+  - if [[ -n $TEST_MODULES ]]; then export DBUS_SESSION_BUS_ADDRESS=/dev/null; export CHROME_BIN=chromium-browser; export DISPLAY=:99.0; sh -e /etc/init.d/xvfb start; sleep 3; fi
 
 script:
   - if [[ -n $TEST_MODULES ]]; then export MODULES="${TEST_MODULES}"; fi