swap arguments are ignored if layout is used for storage

[Andrew Jeffree]

I'm building an OVA where I want to use LVM and have a 32G swap file but currently swap appears to be ignored/not passed to curtin when the config gets evaluated[0] by subiquity and only gets passed if I use config mode which I don't really want to use to just get a larger swap file.

  storage:
    swap:
      size: 32G
    layout:
      name: lvm
      match:
        size: smallest

[0] - https://github.com/canonical/subiquity/blob/main/subiquity/server/controllers/filesystem.py#L601