[model_cards] nlptown/bert-base-multilingual-uncased-sentiment

cc @yvespeirsman
Co-Authored-By: Yves Peirsman <yvespeirsman@users.noreply.github.com>

model_cards/nlptown/bert-base-multilingual-uncased-sentiment/README.md

 ---
-language: english, dutch, german, french, italian, spanish
+language:
+- english
+- dutch
+- german
+- french
+- italian
+- spanish
 ---
 
 # bert-base-multilingual-uncased-sentiment