[pytes collection] Fix flax test collection (#34004)

bit weird but to filter I had to use this

tests/models/resnet/test_modeling_flax_resnet.py

@@ -64,6 +64,7 @@ class FlaxResNetModelTester(unittest.TestCase):
         self.num_labels = num_labels
         self.scope = scope
         self.num_stages = len(hidden_sizes)
+        super().__init__()
 
     def prepare_config_and_inputs(self):
         pixel_values = floats_tensor([self.batch_size, self.num_channels, self.image_size, self.image_size])