Suspected spam user flag

This isn't officially documented but was confirmed by checking a user's flags who had the "Engaged in suspected spam activity" signal

src/Discord/Parts/User/User.php

@@ -70,6 +70,7 @@ class User extends Part implements Stringable
     public const FLAG_VERIFIED_BOT_DEVELOPER = (1 << 17);
     public const FLAG_DISCORD_CERTIFIED_MODERATOR = (1 << 18);
     public const BOT_HTTP_INTERACTIONS = (1 << 19);
+    public const FLAG_SUSPECTED_SPAM = (1 << 20); // Not documented
     public const FLAG_ACTIVE_DEVELOPER = (1 << 22);
 
     public const PREMIUM_NONE = 0;