TF: tests for (de)serializable models with resized tokens (#19013)

* resized models that we can actually load

* separate embeddings check

* add test for embeddings out of bounds

* add fake slows

tests/models/vit_mae/test_modeling_tf_vit_mae.py

@@ -375,6 +375,7 @@ class TFViTMAEModelTest(TFModelTesterMixin, unittest.TestCase):
 
     # overwrite from common since TFViTMAEForPretraining has random masking, we need to fix the noise
     # to generate masks during test
+    @slow
     def test_save_load(self):
         # make mask reproducible
         np.random.seed(2)