docs: rack profile RMS backend requirement

[jayzhudev]

How would you describe the priority of this documentation request

Medium

Please provide a link or source to the relevant docs

https://github.com/NVIDIA/infra-controller/blob/main/book/src/configuration/configurability.md#L199-L318

Describe the problems in the documentation

The docs are not on public documentation site.

(Optional) Propose a correction

No response

Code of Conduct

• I agree to follow NVIDIA Infra Controller's Code of Conduct
• I have searched the open documentation issues and have found no duplicates for this documentation issue