TF generate refactor - Sample (#15793)

* Add TF logits wrappers 

* Add sample method

* add tests for TF logit wrappers

* TF generate sample tests now run on CPU

Co-authored-by: Matt <Rocketknight1@users.noreply.github.com>

tests/test_modeling_tf_common.py

@@ -947,7 +947,7 @@ class TFModelTesterMixin:
 
             if config.bos_token_id is None:
                 # if bos token id is not defined model needs input_ids
-                with self.assertRaises(AssertionError):
+                with self.assertRaises(ValueError):
                     model.generate(do_sample=True, max_length=5)
                 # num_return_sequences = 1
                 self._check_generated_ids(model.generate(input_ids, do_sample=True))