Remove workaround for docker installation

Engine was configured to install docker due to a bug in
Kubespray with Python 3 [1]. This has been solved and
we should let Kubespray handle docker installation.

[1] https://github.com/kubernetes-sigs/kubespray/issues/4300

Change-Id: Iaec2d1d3d7e6087db6bcb2fe7d4b801d1687abf3
3 files changed