Refactor PlayerShopCommand to use Brigadier.

src/main/java/com/alttd/playershops/shop/PlayerShop.java

@@ -10,6 +10,7 @@ import net.kyori.adventure.text.minimessage.tag.resolver.Placeholder;
 import net.kyori.adventure.text.minimessage.tag.resolver.TagResolver;
 import org.bukkit.Bukkit;
 import org.bukkit.Location;
+import org.bukkit.OfflinePlayer;
 import org.bukkit.block.Sign;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.Inventory;
@@ -134,7 +135,7 @@ public class PlayerShop {
         }
     }
 
-    public void setOwner(Player player) {
+    public void setOwner(OfflinePlayer player) {
         ownerUUID = player.getUniqueId();
         ownerName = player.getName();
         update();