restore post_processor for vi

Signed-off-by: Mariana Graterol Fuenmayor <marianag@nvidia.com>

Author: mgrafu

nemo_text_processing/text_normalization/normalize.py

@@ -385,7 +385,7 @@ def normalize(
                 return text
         output = SPACE_DUP.sub(' ', output[1:])
 
-        if self.lang in ["en", "hi"] and hasattr(self, 'post_processor') and self.post_processor is not None:
+        if self.lang in ["en", "hi", "vi"] and hasattr(self, 'post_processor') and self.post_processor is not None:
             output = self.post_process(output)
 
         if punct_post_process: