Purge unused ModelTester code (#37085)

* Purge correctly this time

* Remove more methods from recent PRs

* make fixup

tests/models/convnextv2/test_modeling_convnextv2.py

@@ -119,35 +119,6 @@ class ConvNextV2ModelTester:
         result = model(pixel_values, labels=labels)
         self.parent.assertEqual(result.logits.shape, (self.batch_size, self.num_labels))
 
-    def create_and_check_backbone(self, config, pixel_values, labels):
-        model = ConvNextV2Backbone(config=config)
-        model.to(torch_device)
-        model.eval()
-        result = model(pixel_values)
-
-        # verify hidden states
-        self.parent.assertEqual(len(result.feature_maps), len(config.out_features))
-        self.parent.assertListEqual(list(result.feature_maps[0].shape), [self.batch_size, self.hidden_sizes[1], 4, 4])
-
-        # verify channels
-        self.parent.assertEqual(len(model.channels), len(config.out_features))
-        self.parent.assertListEqual(model.channels, config.hidden_sizes[1:])
-
-        # verify backbone works with out_features=None
-        config.out_features = None
-        model = ConvNextV2Backbone(config=config)
-        model.to(torch_device)
-        model.eval()
-        result = model(pixel_values)
-
-        # verify feature maps
-        self.parent.assertEqual(len(result.feature_maps), 1)
-        self.parent.assertListEqual(list(result.feature_maps[0].shape), [self.batch_size, self.hidden_sizes[-1], 1, 1])
-
-        # verify channels
-        self.parent.assertEqual(len(model.channels), 1)
-        self.parent.assertListEqual(model.channels, [config.hidden_sizes[-1]])
-
     def prepare_config_and_inputs_for_common(self):
         config_and_inputs = self.prepare_config_and_inputs()
         config, pixel_values, labels = config_and_inputs