add image pull policy

 * cause image pull to always happen so that the latest image of the
   current tag is used
 * add some test text to show this new policy working

Author: JunAishima

prefect.yaml

@@ -32,4 +32,5 @@ deployments:
         container_create_kwargs:
           userns_mode: "keep-id:uid=402958,gid=402958"  # workflow-chx:workflow-chx
         auto_remove: true
+        image_pull_policy: Always
       name: chx-work-pool-docker

processing.py

@@ -25,6 +25,7 @@ def process_run(ref):
     full_uid = run.start["uid"]
     logger.info(f"{full_uid = }")
     logger.info("Do something with this uid")
+    logger.info("Now do something else with this uid")
     # Do some additional processing or call otehr python processing functions