[export_cpp] error in export of Add operator

What commit version of aidge do you use

• aidge_core: 0.2.2

• aidge_export_cpp 0.1.2

  both on branch dev

Problem description

When trying to export a model with an add operator, generates an error because of wrong attribute name.

'self.parents[0]' is only present for operator "Add", all the others have 'self.inputs[0]'.

Traceback (most recent call last):
  File "", line 103, in <module>
    aidge_export_cpp.export("export_cpp",model, scheduler)
  File "~/aidge_export_cpp/export.py", line 58, in export
    list_actions = op.forward(list_actions)
                   ^^^^^^^^^^^^^^^^^^^^^^^^
  File "~/aidge_export_cpp/operators.py", line 259, in forward
    inputs1_name=self.parents[0].name() if self.parents[0] else self.name + "_input1",
                                           ^^^^^^^^^^^^
AttributeError: 'AddCPP' object has no attribute 'parents'