Add Ru-Kahn's sfw ref link

media/attribution.js

@@ -20430,7 +20430,7 @@ const attributionData = {
             prefix: "./media/characters/ru-kahn/",
             files: [
                 { name: "front-nsfw.svg", source: "https://www.furaffinity.net/view/36922324/", nsfw: true },
-                { name: "front-sfw.svg", source: null, nsfw: false },
+                { name: "front-sfw.svg", source: "https://www.furaffinity.net/view/36922920/", nsfw: false },
             ],
             authors: [
                 "kokoro-doll"