draft: schedule to run monthly

ci/Jenkinsfile

@@ -5,9 +5,7 @@ pipeline {
         kubernetes {
             yamlFile 'ci/podTemplate.yaml'
             defaultContainer 'buildroot'
-            workspaceVolume persistentVolumeClaimWorkspaceVolume(
-                claimName: 'jenkins-ws-pythonctnr'
-            )
+            workspaceVolume dynamicPVC()
         }
     }
 
@@ -16,20 +14,13 @@ pipeline {
         disableConcurrentBuilds()
     }
 
-    parameters {
-        booleanParam \
-            name: 'Clean',
-            description: 'Clean the workspace and perform a full rebuild'
+    triggers {
+        cron 'TZ=America/Chicago\nH H H * *'
     }
 
     stages {
         stage('Prepare') {
             steps {
-                script {
-                    if (params.Clean) {
-                        sh 'rm -rf _build'
-                    }
-                }
                 checkout poll: false, scm: [
                     $class: 'GitSCM',
                     branches: [[name: '2022.05.x']],