Typo in operator.mustache and downstream files

[ClementPhan]

Description of the modifications

There is a typo in the mustache file for new operators ; most of all operator files have it:

@property
def outputs(self):
    """Enables to get outputs of the operator by evaluationg it
    Returns
    --------
    outputs : Outputs{{capital_class_name}}
    """
    return super().outputs

The docstring should instead read evaluating

Useful links and references

operator.mustache