Fix issue when creating sign with own name without existing account

This was only an issue if the autofill functionality for the own name wasn't used.
Now if there is no account with a certain name then the player can use it if it matches their user name

src/main/java/com/Acrobot/ChestShop/UUIDs/NameManager.java

@@ -287,6 +287,11 @@ public class NameManager implements Listener {
         ChestShop.callEvent(queryEvent);
         Account account = queryEvent.getAccount();
         if (account == null) {
+            // There is no account by the provided name, but it matches the player name
+            // Return true as they specified their own name and a new account should get created
+            if (player.getName().equalsIgnoreCase(name)) {
+                return true;
+            }
             ChestShop.logDebug(player.getName() + " cannot use the name " + name + " for a shop as no account with that name exists");
             return false;
         }