Change command of python and helm in Jenkinsfile

Jenkinsfile

@@ -30,14 +30,20 @@ spec:
   - name: python
     image: docker.local/ci/python:latest
     imagePullPolicy: Always
-    command: ["cat"]
+    command:
+    - sleep
+    args:
+    - 99d
   - name: helm
     image: docker.local/ci/helm:latest
     imagePullPolicy: Always
     env:
     - name: KUBECONFIG
       value: /home/jenkins/agent/workspace/gitea-bme_covidok-backend_master/ci/kube.config
-    command: ["cat"]
+    command:
+    - sleep
+    args:
+    - 99d
 ''') {
 
     node(POD_LABEL) {