Update phishing_email_detection_gpt2.py

Correct metric to rank by (binary accuracy) ...

Author: david-thrower

phishing_email_detection_gpt2.py

@@ -279,7 +279,7 @@ def from_config(cls, config):
     labels=train_labels,
     validation_split=0.35,
     direction='maximize',
-    metric_to_rank_by="val_accuracy",
+    metric_to_rank_by="val_binary_accuracy",
     minimum_levels=minimum_levels,
     maximum_levels=maximum_levels,
     minimum_units_per_level=minimum_units_per_level,