Into "Continuous Integration Server URL".
And the description should be:
URL of the project on the CI server. Leave blank to take this value from pom.xml.
Example: "Jenkins:https://ci.jenkins-ci.org/view/Jenkins%20core/job/jenkins_main_trunk/"or "Bamboo:http://ci.codehaus.org/browse/SONAR".
At the same time, replace "Hudson" by "CI server" whenever it can be found, like in the description of the "sonar.build-stability.use_jsecuritycheck" property.