[Doctest] Fixing doctest bert_generation configuration (#19558)

* Added (with random weights) in the comment before model initialization line

* Added configuration_bert_generation.py to utils/documentation_tests.txt
Co-authored-by: vishwaspai <vishwas.pai@emplay.net>

src/transformers/models/bert_generation/configuration_bert_generation.py

@@ -72,7 +72,7 @@ class BertGenerationConfig(PretrainedConfig):
     >>> # Initializing a BertGeneration config
     >>> configuration = BertGenerationConfig()
 
-    >>> # Initializing a model from the config
+    >>> # Initializing a model (with random weights) from the config
     >>> model = BertGenerationEncoder(configuration)
 
     >>> # Accessing the model configuration

utils/documentation_tests.txt

@@ -22,6 +22,7 @@ src/transformers/models/beit/modeling_beit.py
 src/transformers/models/bert/configuration_bert.py
 src/transformers/models/bert/modeling_bert.py
 src/transformers/models/bert/modeling_tf_bert.py
+src/transformers/models/bert_generation/configuration_bert_generation.py
 src/transformers/models/bigbird_pegasus/modeling_bigbird_pegasus.py
 src/transformers/models/big_bird/modeling_big_bird.py
 src/transformers/models/blenderbot/modeling_blenderbot.py