chore: use new testing-tools image (#820)

Author: dervoeti

modules/tutorials/pages/jupyterhub.adoc

@@ -106,7 +106,7 @@ kind: Deployment
         ...
         - name: create-configmap
           resources: {}
-          image: oci.stackable.tech/sdp/testing-tools:0.2.0-stackable0.0.0-dev
+          image: oci.stackable.tech/sdp/testing-tools:0.3.0-stackable0.0.0-dev
           command: ["/bin/bash", "-c"]
           args:
             - |