This will give a completely different name from the groupId - is that really what's wanted? Each will generate its own random-id parts.

Would it be better to:
* only call `getCloudMachineNamer(setup)` once for the obtainOnce method (so store as a variable).
* store the result of `generateNewGroupId()` as a variable.
* add a new method to CloudMachineNamer like `generateNewMachineUniqueNameFromGroupId()` that could just append a suffix?