Fix typo

I have not tested anything, but this was clearly a typo. Should doctests not have caught this?

Author: KronosTheLate

src/composition/models/pipelines.jl

@@ -188,7 +188,7 @@ Names for the component fields are automatically generated unless
 explicitly specified, as in
 
 ```
-Pipeline(endoder=ContinuousEncoder(drop_last=false),
+Pipeline(encoder=ContinuousEncoder(drop_last=false),
          stand=Standardizer())
 ```