[NodeExport] Add node export class

aidge_core/export/node_export.py

@@ -41,13 +41,9 @@ class ExportNode(ABC):
             else:
                 self.inputs_dims.append(None)
 
-        # TODO
         for idx, child_node in enumerate(self.node.get_children()):
             self.outputs.append(child_node)
-            if child_node is not None:
-                self.outputs_dims.append(self.operator.output(idx).dims())
-            else:
-                self.outputs_dims.append(None)
+            self.outputs_dims.append(self.operator.output(idx).dims())
 
     @abstractmethod
     def export(self, export_folder:str, list_configs:list):