Use self.config_tester.run_common_tests() (#31431)

* First testing updating config tests

* Use run_common_tests

tests/models/timm_backbone/test_modeling_timm_backbone.py

@@ -18,7 +18,6 @@ import inspect
 import unittest
 
 from transformers import AutoBackbone
-from transformers.configuration_utils import PretrainedConfig
 from transformers.testing_utils import require_timm, require_torch, torch_device
 from transformers.utils.import_utils import is_torch_available
 
@@ -106,17 +105,15 @@ class TimmBackboneModelTest(ModelTesterMixin, BackboneTesterMixin, PipelineTeste
     has_attentions = False
 
     def setUp(self):
-        self.config_class = PretrainedConfig
+        # self.config_class = PretrainedConfig
+        self.config_class = TimmBackboneConfig
         self.model_tester = TimmBackboneModelTester(self)
-        self.config_tester = ConfigTester(self, config_class=self.config_class, has_text_modality=False)
+        self.config_tester = ConfigTester(
+            self, config_class=self.config_class, has_text_modality=False, common_properties=["num_channels"]
+        )
 
     def test_config(self):
-        self.config_tester.create_and_test_config_to_json_string()
-        self.config_tester.create_and_test_config_to_json_file()
-        self.config_tester.create_and_test_config_from_and_save_pretrained()
-        self.config_tester.create_and_test_config_with_num_labels()
-        self.config_tester.check_config_can_be_init_without_params()
-        self.config_tester.check_config_arguments_init()
+        self.config_tester.run_common_tests()
 
     def test_timm_transformer_backbone_equivalence(self):
         timm_checkpoint = "resnet18"