Fix spotify regex

PlayBot/sites/spotify.pm

@@ -12,7 +12,7 @@ my $endpoint = "https://api.spotify.com/v1/tracks/";
 
 sub regex
 {
-    return qr#(?:^|[^!])https?://(open|play).spotify.com/track/([a-zA-Z0-9_-]+)#;
+    return qr#(?:^|[^!])https?://(?:open|play).spotify.com/track/([a-zA-Z0-9_-]+)#;
 }
 
 sub get {