Wrap maven-parent in a script block.

Jenkinsfile

@@ -157,6 +157,7 @@ pipeline {
         // the maven-parent needs to be built (once) at each execution
         stage('build maven-parent') {
             steps {
+                script {
                     if ( ('true'.equals(${resume})) && (wasSuccess('maven-parent')) ) {
                         // propagate success
                         sh "echo -e \\\"maven-parent,SUCCESS\\\">> $JOB_REPORT"
@@ -171,6 +172,7 @@ pipeline {
                     }
                 }
             }
+        }
         stage('build components') {
             steps {
                 script {