Update README.md

demos/text_to_speech/README.md

 
+
 # TTS (Text To Speech)
 
 ## Introduction
@@ -39,8 +40,7 @@ Input of this demo should be a text of the specific language that can be passed
 	paddlespeech tts --am fastspeech2_vctk --voc pwgan_vctk --input "hello, boys" --lang en --spk_id 0
     	```
      You can change `spk_id` here.
-	   
-  Usage:
+ Usage:
   
   ```bash
   paddlespeech tts --help