Fix AttributeError in huggingface.py When 'model_type' is Missing (#1489)

* model_type attribute error

Getting attribute error when using a model without a 'model_type'

* fix w/ and w/out the 'model_type' specification

* use getattr(), also fix other config.model_type reference

* Update huggingface.py

---------
Co-authored-by: Hailey Schoelkopf <65563625+haileyschoelkopf@users.noreply.github.com>

lm_eval/models/huggingface.py

@@ -250,7 +250,7 @@ class HFLM(TemplateLM):
         elif self.tokenizer.eos_token:
             self.tokenizer.pad_token_id = self.tokenizer.eos_token_id
         else:
-            if self.config.model_type == "qwen":
+            if getattr(self.config, "model_type", None) == "qwen":
                 # Qwen's trust_remote_code tokenizer does not allow for adding special tokens
                 self.tokenizer.pad_token = "<|endoftext|>"
             elif (
@@ -268,11 +268,11 @@ class HFLM(TemplateLM):
 
         # TODO: override this for Gemma
         self.add_bos_token = add_bos_token
-        if self.config.model_type == "gemma":
+        if getattr(self.config, "model_type", None) == "gemma":
+            self.add_bos_token = True
             eval_logger.info(
-                "Model is of type 'gemma', will use a BOS token as Gemma underperforms without it."
+                f"Model type is '{self.config.model_type}', a BOS token will be used as Gemma underperforms without it."
             )
-            self.add_bos_token = True
 
         self._max_length = max_length