Current implementation of GPUs in Notebook prevent auto-scaling from working for GPU nodes

Description of problem:

In JupyterHub, currently, a user only sees the GPU drop-down if 

1) there are GPU nodes running
2) there are spare GPUs that are not used by anyone

This means that if I have an AutoScaling GPU node pool with min=1 and max=10, I will have 1 available GPU. If user A grabs that GPU, when user B comes in, the GPU drop down will not be displayed. Therefore, user B will not be able to trigger the auto-scaling. 

Prerequisites (if any, like setup, operators/versions):

RHODS v 1.13 

Steps to Reproduce

1. Get user A to grab the only GPU available
2. Confirm that user B is no longer shown the GPU option

Actual results:

GPU dropdown is only visible if there are GPUs available. 

Expected results:

GPU dropdown should be visible even if there are no GPUs available currently, because the action of asking for one, even if unavailable, can trigger the addition of another GPU machine. (auto-scaling). 

Reproducibility (Always/Intermittent/Only Once):

Always

Build Details:

RHODS 1.13. 

Workaround:

Not using autoscaling and always having a lot of GPU machines, which is very costly. 

Additional info: