Removed Russian

There was no translations for Russian available in the project

docs/languages.json

@@ -9,11 +9,6 @@
         {
             "name": "한국어 (Korean)",
             "translation": "Translation by Kiman Kim"
-        },
-        "ru":
-        {
-            "name": "Ру́сский (Russian)",
-            "translation": ""
         }
     }
 }