[Tests] reduce the model size in the dit test

tests/pipelines/dit/test_dit.py

@@ -47,10 +47,10 @@ class DiTPipelineFastTests(PipelineTesterMixin, unittest.TestCase):
     def get_dummy_components(self):
         torch.manual_seed(0)
         transformer = Transformer2DModel(
-            sample_size=16,
-            num_layers=2,
-            patch_size=4,
-            attention_head_dim=8,
+            sample_size=2,
+            num_layers=1,
+            patch_size=1,
+            attention_head_dim=2,
             num_attention_heads=2,
             in_channels=4,
             out_channels=8,
@@ -90,8 +90,8 @@ def test_inference(self):
         image = pipe(**inputs).images
         image_slice = image[0, -3:, -3:, -1]
 
-        self.assertEqual(image.shape, (1, 16, 16, 3))
-        expected_slice = np.array([0.2946, 0.6601, 0.4329, 0.3296, 0.4144, 0.5319, 0.7273, 0.5013, 0.4457])
+        self.assertEqual(image.shape, (1, 2, 2, 3))
+        expected_slice = np.array([0.485, 0.6022, 0.5567, 0.6807])
         max_diff = np.abs(image_slice.flatten() - expected_slice).max()
         self.assertLessEqual(max_diff, 1e-3)