CP4D 5.1.x doesn't appear to be compatible with ws-runtime-231

[David-M-IBM]

I couldn't get ws-runtimes to install on OCP 4.16 with CP4D 5.1.0 without removing the following values from the config:

- ibm-cpd-ws-runtime-231-py
- ibm-cpd-ws-runtime-231-pygpu
- ibm-cpd-ws-runtime-231-r

I made a PR with those values removed from the sample config and I'm not sure if any other values should be added. This was the only relevant section I could find in the install docs where there was a list of valid names. I did find this doc that says 23.1 isn't included in IBM Software Hub.

Let me know if I am missing some and/or where I can find the list and I'll add them to the PR.