Revert "Fix Operator.eval() in case output pin 0 is not named "fields_container" (#1527)"

This reverts commit b777188.

Author: PProfizi

src/ansys/dpf/core/outputs.py

@@ -112,9 +112,6 @@ def _get_given_output(self, input_type_name):
                         corresponding_pins.append(pin)
         return corresponding_pins
 
-    def __getitem__(self, index):
-        return self._outputs[index]
-
     def __str__(self):
         docstr = "Available outputs:\n"
         for output in self._outputs:

src/ansys/dpf/core/results.py

@@ -263,12 +263,7 @@ def eval(self):
         >>> fc = disp.on_all_time_freqs.eval()
 
         """
-        outputs = self.__call__().outputs
-        if hasattr(outputs, "fields_container"):
-            fc = outputs.fields_container()
-        else:
-            # Support operators where the first output is not named "field_container"
-            fc = outputs[0]()
+        fc = self.__call__().outputs.fields_container()
         if self._specific_fc_type == "shape":
             fc = ElShapeFieldsContainer(fields_container=fc._get_ownership(), server=fc._server)
         elif self._specific_fc_type == "body":