Fix missing outputs dims for last layer

aidge_core/export/node_export.py

@@ -43,7 +43,9 @@ class ExportNode(ABC):
 
         for idx, child_node in enumerate(self.node.get_children()):
             self.outputs.append(child_node)
-            self.outputs_dims.append(self.operator.output(idx).dims())
+        
+        # Dirty hot fix, change it quickly
+        self.outputs_dims.append(self.operator.output(0).dims())
 
     @abstractmethod
     def export(self, export_folder:str, list_configs:list):