Stop pressurizer pumping a cold loop

tests/test_pressurizer.py

@@ -5,14 +5,15 @@ from reactor_sim.commands import ReactorCommand
 def test_pressurizer_raises_pressure_with_level():
     reactor = Reactor.default()
     state = reactor.initial_state()
-    state.primary_loop.pressure = 5.0
+    state.primary_loop.pressure = 0.5
     reactor.pressurizer_level = 0.8
     reactor.primary_pump_active = False
     reactor.secondary_pump_active = False
+    reactor.shutdown = False
 
-    reactor.step(state, dt=1.0, command=ReactorCommand.scram_all())
+    reactor.step(state, dt=1.0, command=ReactorCommand())
 
-    assert state.primary_loop.pressure > 5.0
+    assert state.primary_loop.pressure > 0.5
     assert reactor.pressurizer_level < 0.8