openshift: Properly filter unsupported grub config

[travier]

WIP as this fails tests but I don't yet understand why

[Roshan-R]

Example butane configuration for testing unsupported grub config

variant: openshift
version: 4.18.0
metadata:
  name: test-grub-block
  labels:
    machineconfiguration.openshift.io/role: worker
grub:
  users:
    - name: root
      password_hash: "$6$abcd"  # Just a dummy hash

[travier]

Hum, if we do this correctly, the docs for the GRUB part should disappear from the openshift specs.

[travier]

i.e. we should not need the workaround in https://github.com/coreos/butane/blob/main/internal/doc/butane.yaml#L357 anymore

[Roshan-R]

Hum, if we do this correctly, the docs for the GRUB part should disappear from the openshift specs.

I am a bit confused on that area. As far as I can understand, openshift 4.20.0-experimental has the translateUserGrubCfg function to handle the $.grub path. So shouldn't that warrant it to be documented in internal/doc/butane.yaml? Or am I missing something obvious.

[travier]

It's only implemented in this experimental version of the spec. For all the others, it should not be mentioned in the docs at all.

[travier]

I tried things in main...travier:butane:ocp-grub-unsupported-wip but that's not correct either.

[travier]

We need to find the correct way to filter it completely from the docs as well as have it fail during validation.