Leap15 build fails due to missing gzip

[Walt Boring]

Running a build of Leap15 images fails due to missing gzip package.

...
(50/50) Installing: git-core-2.16.4-lp150.2.9.1.x86_64 [............done]
Executing %posttrans script 'blog-2.18-lp150.4.2.x86_64.rpm' [...
Output of systemd-presets-common-SUSE-15-lp150.1.1.noarch.rpm %posttrans script:
    Created symlink /etc/systemd/system/default.target.wants/ca-certificates.path -> /usr/lib/systemd/system/ca-certificates.path.
    Created symlink /etc/systemd/system/default.target.wants/ca-certificates.service -> /usr/lib/systemd/system/ca-certificates.service.
    Created symlink /etc/systemd/system/multi-user.target.wants/kbdsettings.service -> /usr/lib/systemd/system/kbdsettings.service.

.....
Output of udev-234-lp150.20.15.1.x86_64.rpm %posttrans script:
    Creating /lib/udev -> /usr/lib/udev symlink.

..done]
+ [[ cinder == \r\e\q\u\i\r\e\m\e\n\t\s ]]
++ dirname /opt/loci/scripts/install.sh
+ /opt/loci/scripts/fetch_wheels.sh
+ [[ yes == \n\o ]]
+ python=python3
++ dirname /opt/loci/scripts/fetch_wheels.sh
+ python3 /opt/loci/scripts/fetch_wheels.py
http://auth.docker.io/token?service=registry.docker.io&scope=repository:loci/requirements:pull
http://registry.hub.docker.com/v2/loci/requirements/manifests/master-ubuntu
http://registry.hub.docker.com/v2/loci/requirements/blobs/sha256:137e085246fa33bd1e963241dd1a8efb6a9ec1cac1d0ea31bf99382b684a90c0
+ mkdir -p /tmp/wheels/
+ tar xf /tmp/wheels.tar.gz '--exclude=.*' -C /tmp/wheels/
tar (child): gzip: Cannot exec: No such file or directory
tar (child): Error is not recoverable: exiting now
tar: Child returned status 2
tar: Error is not recoverable: exiting now
Removing intermediate container fd871f550000