Mark all `BridgeTower` tests slow for now (#22039)

* slow me

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Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>

tests/models/bridgetower/test_modeling_bridgetower.py

@@ -202,6 +202,7 @@ class BridgeTowerModelTester:
         return config, inputs_dict
 
 
+@slow
 @require_torch
 @unittest.skipIf(not is_torch_greater_or_equal_than_1_10, "BridgeTower is only available in torch v1.10+")
 class BridgeTowerModelTest(ModelTesterMixin, PipelineTesterMixin, unittest.TestCase):
@@ -494,6 +495,7 @@ class BridgeTowerModelIntegrationTest(unittest.TestCase):
         self.assertEqual(outputs.logits.shape, expected_shape)
 
 
+@slow
 @require_torch
 @unittest.skipIf(not is_torch_greater_or_equal_than_1_10, "BridgeTower is only available in torch v1.10+")
 class BridgeTowerModelTrainingTest(unittest.TestCase):