Added mutate module to sci-kit example to show the same functionality, also uses module override

Author: jernejfrank

docs/reference/decorators/pipe.rst

@@ -3,9 +3,7 @@ pipe family
 =======================
 
 We have a family of decorators that can help with transforming the input and output of a node in the DAG.
-For some examples have a look at:
-- pipe_input and pipe_output: https://github.com/DAGWorks-Inc/hamilton/tree/main/examples/scikit-learn/species_distribution_modeling
-- mutate(TBD): https://github.com/DAGWorks-Inc/hamilton/tree/main/examples/mutate/feature_experimentation
+For some examples have a look at: https://github.com/DAGWorks-Inc/hamilton/tree/main/examples/scikit-learn/species_distribution_modeling
 
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