add prepare_inputs_for_generation

modeling.py

@@ -11,3 +11,8 @@ class NewModelForCausalLM(BertModel):
     def __init__(self, config):
         super().__init__(config)
         self.last_layer = torch.nn.Linear(config.hidden_size, config.new_hidden_size)
+
+    # prior to v4.45, overwriting `prepare_inputs_for_generation` was a hard requirement for a model to be
+    # `generate`-compatible
+    def prepare_inputs_for_generation(self):
+        pass