In the **Install using the repository** section, the GPG implied location was identified as `<DOCKER-EE-URL>/sles/12.3/<ARCHITECTURE>/stable-<VERSION>/sles/gpg` which does not exist. The correct location is `<DOCKER-EE-URL>/sles/gpg`. I introduce a second variable here called `DOCKER_EE_BASE_URL` which will be used to distinguish between the root level of the directory and aid in correctly locating the gpg key for the `rpm --import` command.
The CentOS, Red Hat, and Fedora package-repositories contain
several versions of the docker package. Some of those were
missing from the list of packages to uninstall, and could
conflict with the docker-ce/docker-ee package.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>