Update NameChecker to handle blank owner names

This commit updates the NameChecker in the ChestShopListener, ensuring that when a blank owner name is provided, it defaults to the player's unique ID. This change facilitates smoother store creation for players and improves data consistency.

src/main/java/com/Acrobot/ChestShop/Listeners/PreShopCreation/NameChecker.java

@@ -22,7 +22,7 @@ public static void onPreShopCreation(PreShopCreationEvent event) {
         String name = event.getOwnerName();
 
         Player player = event.getPlayer();
-        UUID uuidForFullName = NameManager.getUUIDFor(name);
+        UUID uuidForFullName = name.isBlank() ? player.getUniqueId() : NameManager.getUUIDFor(name);
 
         if (!uuidForFullName.equals(player.getUniqueId()) && Permission.has(player, Permission.ADMIN)) {
             name = NameManager.getFullNameFor(uuidForFullName);