escape regex delimiters in embed.php

embed.php

@@ -86,7 +86,7 @@ $noembed_site = array(
     "https?://www\\.urbandictionary\\.com/define\\.php\\?term=.+",
     "https?://(?:www\\.)?xkcd\\.com/\\d+/?",
     "https?://.*\\.deviantart\\.com/art/.*",
-    "https?://.*\\.deviantart\\.com/.*#/d.*",
+    "https?://.*\\.deviantart\\.com/.*\#/d.*",
     "https?://instagram\\.com/p/.*",
     "https?://instagr\\.am/p/.*",
     "https?://instagram\\.com/p/.*",