docker: Resolve partial update problem in Tumbleweed image.

This resolves the following error:

  ImportError: /usr/lib64/libgobject-2.0.so.0: undefined symbol:
  g_memdup2

* docker/Dockerfile_opensuse-tumbleweed: Do not update and install
stuff in various steps.
* docker/Dockerfile_opensuse-leap_15.2: Likewise.

Change-Id: I286576cddd5226cf40fd1bec997be36b2142e355