Update example reference (#3403)

Signed-off-by: Emmanuel Ferdman <[email protected]>

pyro/contrib/autoname/named.py

@@ -42,9 +42,9 @@
     >>> obs = state.x.sample_(dist.Normal(loc, scale), obs=z)
 
 For deeper examples of how these can be used in model code, see the
-`Tree Data <https://github.com/pyro-ppl/pyro/blob/dev/examples/contrib/named/tree_data.py>`_
+`Tree Data <https://github.com/pyro-ppl/pyro/blob/dev/examples/contrib/autoname/tree_data.py>`_
 and
-`Mixture <https://github.com/pyro-ppl/pyro/blob/dev/examples/contrib/named/mixture.py>`_
+`Mixture <https://github.com/pyro-ppl/pyro/blob/dev/examples/contrib/autoname/mixture.py>`_
 examples.
 
 Authors: Fritz Obermeyer, Alexander Rush