Update phishing_email_detection_gpt2.py

Hard set levels to the known optimum.

Author: david-thrower

phishing_email_detection_gpt2.py

@@ -274,7 +274,7 @@ def from_config(cls, config):
 learning_rate = 0.0000511065
 epochs = 15  # [1, 100]
 batch_size = 20
-minimum_levels = 2
+minimum_levels = 3
 maximum_levels = 3 # [3,7]
 
 minimum_units_per_level = 4