Update log to only print when input and output characters are different

convert_hf_to_gguf.py

@@ -529,8 +529,10 @@ def get_vocab_base(self) -> tuple[list[str], list[int], str]:
                     # used for `\n` / `\t` have been manually added in the added tokens
                     # To avoid unexpected issues - we make sure to encode single-char tokens
                     if len(token) == 1:
-                        logger.info("Ecode-Decode special characters using AutoTokenizer")
+                        previous_token = token
                         token = tokenizer.decode(tokenizer.encode(token, add_special_tokens=False))
+                        if previous_token != token:
+                            logger.info(f"{repr(previous_token)} is encoded and decoded back to {repr(token)} using AutoTokenizer")
 
                     if tokenizer.added_tokens_decoder[i].special or self.does_token_look_special(token):
                         toktypes.append(gguf.TokenType.CONTROL)