CLI: Add new deploy tests

[josephjclark]

We need a nice suite of unit tests on the new project deploy command.

I've been skipping it to get software out early - but we need to come back and tidy this

We need to test stuff like:

• Post an update to an existing projet
• Post with an error on divergence
• Post update workflows but ignore diverged unchanged ones (and don't revert changes!)
• Post a new project
• (later) Post only selected workflows