Secrets should be quiet.

vars/declarativeFunctions.groovy

@@ -40,7 +40,10 @@ def createSecret (Map config) {
         serverUrl: config.kubeURL,
         namespace: config.namespace
     ]) {
-        sh "printf '%s\n' \"" + config.secret + "\" | kubectl apply -f -"
+        sh """
+            set +x
+            printf '%s\n' \"" + config.secret + "\" | kubectl apply -f -"
+        """
     }
 }