Adding parent as upstream trigger

Jenkinsfile

@@ -39,6 +39,11 @@ def defaultPublishers = [artifactsPublisher(disabled: false), junitPublisher(ign
 
 pipeline {
     agent { label "${LABEL}" }
+    // Build should also start, if parent has been built successfully
+    triggers { 
+        upstream(upstreamProjects: 'Archiva-TLP-Gitbox/archiva-parent/master', threshold: hudson.model.Result.SUCCESS) 
+    }
+
     options {
         disableConcurrentBuilds()
         durabilityHint('PERFORMANCE_OPTIMIZED')