fix space

sentencepiece_ja.py

@@ -46,6 +46,10 @@ class SentencePieceJA(PreTrainedTokenizer):
     def _convert_id_to_token(self, index: int) -> str:
         return self._tokenizer.decode([index])
     
+    def convert_tokens_to_string(self, tokens: List[str]) -> str:        
+        ## 日本語用
+        return "".join(tokens)
+
     def save_vocabulary(self, save_directory: str, filename_prefix: Optional[str] = None) -> Tuple[str]:
         index = 0
         if os.path.isdir(save_directory):