Fix bad import of BinaryBinnedAUPRC in metrics.__init__

Differential Revision: D45261566

fbshipit-source-id: 2d3dc373df6f366c8c9373a2e652b6ea96cd4225

Author: bobakfb

torcheval/metrics/__init__.py

@@ -72,6 +72,7 @@
     "BinaryAccuracy",
     "BinaryAUPRC",
     "BinaryAUROC",
+    "BinaryBinnedAUPRC",
     "BinaryBinnedAUROC",
     "BinaryBinnedPrecisionRecallCurve",
     "BinaryConfusionMatrix",