fix: adding folded fold frame creates a fold frame not structural frame

Author: Lachlan Grose

LoopStructural/modelling/core/geological_model.py

@@ -890,7 +890,7 @@ def create_and_add_folded_fold_frame(self, fold_frame_data,
         interpolators = [fold_interpolator, gy_fold_interpolator,
                          frame_interpolator.copy()]
         fold_frame_builder = StructuralFrameBuilder(
-            interpolators=interpolators, name=fold_frame_data, fold=fold, **kwargs)
+            interpolators=interpolators, name=fold_frame_data, fold=fold, frame=FoldFrame,**kwargs)
         fold_frame_builder.add_data_from_data_frame(
             self.data[self.data['feature_name'] == fold_frame_data])