Test in an environment with client and minimal-client dependencies only

[danielballan]

Following up on @pbeaucage in #711:

A broader question as this has happened before: could we add a CI test that installs the package with just [minimal-client] or [client] and verifies (to first order) that the package imports, and ideally that a basic client function test passes, maybe against the public test server? This would likely have to be its own GHA/non-pytest script since afaik there is no environment control at the pytest level.