test: don't initialize self.machine to None
test: don't initialize self.machine to None

This confuses LSP servers and generates plenty of warnings about
self.machine maybe being None. In reality it can never be None as
provision is always initialized with one machine.

martinpitt/cockpit,martinpitt/cockpit,martinpitt/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,martinpitt/cockpit,martinpitt/cockpit,cockpit-project/cockpit,cockpit-project/cockpit