Island: Make machine model hashable

Machines can be hashed based on their ID. This allows us to add them to set for example and make sure no duplicate entries are there

monkey/monkey_island/cc/models/machine.py

@@ -38,3 +38,6 @@ class Machine(MutableInfectionMonkeyBaseModel):
     _make_immutable_sequence = validator("network_interfaces", pre=True, allow_reuse=True)(
         make_immutable_sequence
     )
+
+    def __hash__(self):
+        return self.id