Fix some TF GPT-J CI testings (#16454)

* Fix for test_mixed_precision

* Fix test_saved_model_creation by using shape_list instead of shape

* skit test_model_from_pretrained on GPU for now to avoid GPU OOM

* skip test_gptj_sample_max_time for now

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

tests/gptj/test_modeling_tf_gptj.py

@@ -345,6 +345,10 @@ class TFGPTJModelTest(TFModelTesterMixin, TFCoreModelTesterMixin, unittest.TestC
                 assert name is None
 
     @slow
+    @unittest.skipIf(
+        not is_tf_available() or len(tf.config.list_physical_devices("GPU")) > 0,
+        "skip testing on GPU for now to avoid GPU OOM.",
+    )
     def test_model_from_pretrained(self):
         model = TFGPTJModel.from_pretrained("EleutherAI/gpt-j-6B", from_pt=True)
         self.assertIsNotNone(model)
@@ -395,6 +399,7 @@ class TFGPTJModelLanguageGenerationTest(unittest.TestCase):
         )  # token_type_ids should change output
 
     @slow
+    @unittest.skip(reason="TF generate currently has no time-based stopping criteria")
     def test_gptj_sample_max_time(self):
         tokenizer = AutoTokenizer.from_pretrained("anton-l/gpt-j-tiny-random")
         model = TFGPTJForCausalLM.from_pretrained("anton-l/gpt-j-tiny-random", from_pt=True)