Clarify storage blob data contributor role instructions

Updating bolding and language

Author: renaaliu

articles/ai-services/language-service/custom-named-entity-recognition/includes/use-pre-existing-resource.md

@@ -51,7 +51,7 @@ Make sure to enable **Custom text classification / Custom Named Entity Recogniti
 5. Select **Apply**.
 
 >[!Important]
-> * Make sure that the user has storage blob data contributor role assigned for the user making the changes.
+> Make sure that the user making changes has **storage blob data contributor role** assigned for them.
 
 ### Add required roles