Update Jenkinsfile to run statistics only if necessary

Jenkinsfile

@@ -39,6 +39,16 @@ pipeline {
     }
     
     stage ('Reports and Statistics') {
+      //create reports only if triggerd by new code
+      when {
+        expression {
+          if(currentBuild.rawBuild.getCauses().any { it ==~ /^jenkins\.branch\.BranchIndexingCause.*/}){
+            return true
+          }
+          return false
+        }
+      }
+
       steps {
         script {
           projver=sh(returnStdout: true, script: 'mvn org.apache.maven.plugins:maven-help-plugin:2.1.1:evaluate -Dexpression=project.version | grep -Ev "(^\\[|Download\\w+)"').trim()