Warlock Soul Shard Hotfix (#1442)

Hello everyone,

This PR is to address an issue that was posted recently - a player has shown that soul shards are being created in excess, spamming the player's chat log. I am adding an isuseful() check to the createsoulshard action, so it will never be executed if they have more than 5 soul shards.

Also, out of an abundance of caution, I am lowering the cap for CastDrainSoulAction::isUseful() to 20 from 32. That way, if for some reason the warlock has 20+ shards, it won't attempt to collect any more / use drain soul.

src/strategy/warlock/WarlockActions.h

@@ -46,6 +46,7 @@ class CreateSoulShardAction : public Action
 public:
     CreateSoulShardAction(PlayerbotAI* botAI) : Action(botAI, "create soul shard") {}
     bool Execute(Event event) override;
+    bool isUseful() override;
 };
 
 class DestroySoulShardAction : public InventoryAction