The CUDA (gpu minimal) image build SHOULD still happen at install-time.  We just need to remove the special annotation on the imagestream that allows it to show-up in the spawner UI.

All other images/imagestreams should be unchanged (ie:  we DO still want to build AND see TF/PyTorch).

Acceptance criteria: 

• The cuda build is still executed as part of the install time build chain.  
• The plain cuda image (gpu minimal) is NOT present in the Jupyter Spawner