don't showing 3 buttons for sharpsh. upgr. (gelu)

lib/gameState/UpgradeInfo.cpp

@@ -15,6 +15,9 @@ VCMI_LIB_NAMESPACE_BEGIN
 
 void UpgradeInfo::addUpgrade(const CreatureID & upgradeID, const Creature * creature, int costPercentageModifier)
 {
+	if(vstd::contains(upgradesIDs, upgradeID))
+		return;
+
 	isAvailable = costPercentageModifier >= 0;
 
 	upgradesIDs.push_back(upgradeID);