Revert "Update ubuntu docker image for packagecloud_push"

This reverts commit e6b48997726fecfc3d1b323d8c572fd3db4ee13d.

Reason for revert: After merge jobs IMMEDIATELY started failing with errors like this:

14:23:33 /tmp/jenkins2645739511333024262.sh: line 81: docker: command not found 

Change-Id: If69a9c3582d97db50258b1458c6e80902bec238d
Signed-off-by: Christopher Lott <cl778h@att.com>
diff --git a/jenkins-config/clouds/openstack/cattle/ubuntu1804-docker-4c-4g.cfg b/jenkins-config/clouds/openstack/cattle/ubuntu1804-docker-4c-4g.cfg
index 92be8b1..9eec453 100644
--- a/jenkins-config/clouds/openstack/cattle/ubuntu1804-docker-4c-4g.cfg
+++ b/jenkins-config/clouds/openstack/cattle/ubuntu1804-docker-4c-4g.cfg
@@ -1,4 +1,4 @@
-IMAGE_NAME=ZZCI - Ubuntu 18.04 - docker - x86_64 - 20190810-081742.446
+IMAGE_NAME=ZZCI - Ubuntu 18.04 - docker - x86_64 - 20190419-225102.176
 LABELS=ubuntu1804-docker-4c-4g
 HARDWARE_ID=v2-highcpu-4
 VOLUME_SIZE=10
\ No newline at end of file