Add multilingual to the language tag

Hi! A PR to add multilingual to the language tag to improve the referencing.

README.md

@@ -1,13 +1,12 @@
 ---
-license: apache-2.0
 language:
 - ru
 - sv
-
+- multilingual
+license: apache-2.0
 tags:
 - generated_from_trainer
 - translation
-
 model-index:
 - name: mt-ru-sv-finetuned
   results: []