Fix 'DiscoverUM3Action' required attention from user in flow. [CURA-6057]

cura/MachineAction.py

@@ -33,6 +33,12 @@ class MachineAction(QObject, PluginObject):
     def getKey(self) -> str:
         return self._key
 
+    ## Whether this action needs to ask the user anything.
+    #  If not, we shouldn't present the user with certain screens which otherwise show up.
+    #  Defaults to true to be in line with the old behaviour.
+    def needsUserInteraction(self) -> bool:
+        return True
+
     @pyqtProperty(str, notify = labelChanged)
     def label(self) -> str:
         return self._label

cura/UI/WelcomePagesModel.py

@@ -221,7 +221,7 @@ class WelcomePagesModel(ListModel):
 
         definition_id = global_stack.definition.getId()
         first_start_actions = self._application.getMachineActionManager().getFirstStartActions(definition_id)
-        return len(first_start_actions) > 0
+        return len([action for action in first_start_actions if action.needsUserInteraction()]) > 0
 
     def addPage(self) -> None:
         pass

plugins/UM3NetworkPrinting/src/DiscoverUM3Action.py

@@ -41,6 +41,11 @@ class DiscoverUM3Action(MachineAction):
         # Time to wait after a zero-conf service change before allowing a zeroconf reset
         self._zero_conf_change_grace_period = 0.25 #type: float
 
+    # Overrides the one in MachineAction.
+    # This requires not attention from the user (any more), so we don't need to show any 'upgrade screens'.
+    def needsUserInteraction(self) -> bool:
+        return False
+
     @pyqtSlot()
     def startDiscovery(self):
         if not self._network_plugin: