[Doctest] Add `configuration_resnet.py` (#19620)

* ResNet Config for doctest

* added empty lines as suggested

* ran make style

src/transformers/models/resnet/configuration_resnet.py

@@ -65,8 +65,10 @@ class ResNetConfig(PretrainedConfig):
 
     >>> # Initializing a ResNet resnet-50 style configuration
     >>> configuration = ResNetConfig()
-    >>> # Initializing a model from the resnet-50 style configuration
+
+    >>> # Initializing a model (with random weights) from the resnet-50 style configuration
     >>> model = ResNetModel(configuration)
+
     >>> # Accessing the model configuration
     >>> configuration = model.config
     ```

utils/documentation_tests.txt

@@ -90,6 +90,7 @@ src/transformers/models/reformer/configuration_reformer.py
 src/transformers/models/reformer/modeling_reformer.py
 src/transformers/models/regnet/modeling_regnet.py
 src/transformers/models/regnet/modeling_tf_regnet.py
+src/transformers/models/resnet/configuration_resnet.py
 src/transformers/models/resnet/modeling_resnet.py
 src/transformers/models/resnet/modeling_tf_resnet.py
 src/transformers/models/roberta/configuration_roberta.py