[2.5, RBAC, UI, API] Operator/admin can't edit storage for machines

[webteam-app]

Bug originally filed by bjornt at https://bugs.launchpad.net/bugs/1811232

This is testing with MAAS 2.5.1-7489-g2f25a2cc0-0ubuntu1~18.04.1.

Logged in as a user that has either the Operator or Admin role in RBAC
for the resource pool the machine belongs to, I can't edit
the storage of machines in the pool.

I should be able to admin the machine, and I can indeed modify the
network settings.

This applies to both the UI and the API. Although in the API, you
can create and delete partitions, but you can't format or mount them.

[Caleb-Ellis]

We can think this has been fixed as part of the React migration