[Misc] Try to configure sonarqube analysis so that tests in one modul…

…e that indirectly exercise code in other modules are counted

Jenkinsfile

@@ -78,11 +78,19 @@ stage ('Commons Builds') {
     'quality': {
       node {
         // Run the quality checks.
+        // Sonar notes:
+        // - we need sonar:sonar to perform the analysis
+        // - we need sonar = true to push the analysis to Sonarcloud
+        // - we need jacoco:report to execute jacoco and compute test coverage
+        // - we need -Pcoverage and -Dxwiki.jacoco.itDestFile to tell Jacoco to compute a single global Jacoco
+        //   coverage for the full reactor (so that the coverage percentage computed takes into account module tests
+        //   which cover code in other modules)
         xwikiBuild('Quality') {
           xvnc = false
           mavenOpts = globalMavenOpts
           goals = 'clean install jacoco:report sonar:sonar'
-          profiles = 'quality,legacy'
+          profiles = 'quality,legacy,coverage'
+          properties = '-Dxwiki.jacoco.itDestFile=`pwd`/target/jacoco-it.exec'
           sonar = true
           javadoc = false
         }