Make the local repo path available through an environment variable.

Jenkinsfile

@@ -41,6 +41,7 @@ pipeline {
    // see https://jenkins.io/doc/book/pipeline/syntax/#environment
    environment {
       JOB_OPTIONS = "${options}"
+      MAVEN_LOCAL_REPO = "${maven_local_repo_path}"
    }
 
    // see https://jenkins.io/doc/book/pipeline/syntax/#parameters
@@ -55,8 +56,8 @@ pipeline {
         stage('clean up before starting') {
             script {
                 echo "Create a fresh local repository"
-                rm -rf "${maven_local_repo_path}"
-                mkdir -p "${maven_local_repo_path}"
+                rm -rf $MAVEN_LOCAL_REPO
+                mkdir -p $MAVEN_LOCAL_REPO
                 echo "Done with local repository"
             }
         }