Prevent ability to enable copy/paste from Guacamole VMs

[jonnyry]

Background

SATRE requirement 2.1.1 states:

2.1.1: You must not allow users to copy data out of your TRE via the system clipboard.
A TRE user must not be able to copy sensitive data out of a workspace using the system clipboard. A TRE may allow user to paste text into a workspace. This might not be relevant to your TRE, for example if your user interface does not have a clipboard.

The TRE does provide the ability for an administrator or workspace owner to restrict copy/paste functionality within Virtual Machines, by checking the "Disable Copy" and "Disable Paste" boxes during machine creation:

However as per https://github.com/nwsde/nwsde-satre/issues/43 this should be locked down further.

Implementation

Disable the ability to provision VMs with copy/paste facility:

• grey out the "Disable 'Copy'" and "Disable 'Paste'" checkboxes
• enforce this in backend infrastructure code, to ensure it can't be overriden