change prod ckan image and remove sudo command

ckan/Dockerfile

@@ -1,4 +1,4 @@
-FROM ckan/ckan:2.9.10
+FROM ckan/ckan-base:2.9.10
 
 LABEL maintainer='[email protected]'
 

ckan/start_ckan.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 
 # Run the prerun script to init CKAN and create the default admin user
-sudo -u ckan -EH python3 prerun.py
+ckan -EH python3 prerun.py
 
 # Run any startup scripts provided by images extending this one
 if [[ -d "/docker-entrypoint.d" ]]
@@ -21,7 +21,7 @@ then
     # Start supervisord
     supervisord --configuration /etc/supervisord.conf &
     # Start uwsgi
-    sudo -u ckan -EH uwsgi uwsgi.ini
+    ckan -EH uwsgi uwsgi.ini
 else
   echo "[prerun] failed...not starting CKAN."
 fi