Add ZCH modules to TorchRec bento kernel (pytorch#3249)

Summary:
Pull Request resolved: pytorch#3249

Can be used for faster prototyping in notebook

Reviewed By: spmex

Differential Revision: D79439896

fbshipit-source-id: 83e734e4166d4136cb204029cf698465d56fe74b

Author: kausv

torchrec/__init__.py

@@ -21,6 +21,11 @@
     EmbeddingBagCollectionInterface,
     EmbeddingCollection,
 )  # noqa
+from torchrec.modules.hash_mc_modules import HashZchManagedCollisionModule  # noqa
+from torchrec.modules.mc_embedding_modules import (  # noqa
+    ManagedCollisionEmbeddingBagCollection,
+    ManagedCollisionEmbeddingCollection,
+)
 from torchrec.sparse.jagged_tensor import (  # noqa
     JaggedTensor,
     KeyedJaggedTensor,