Can’t set the booking unit cost to 0

Hi,

Thank you for your plugin and your support. When you set the booking unit cost to 0 (for example when you want to make an offer and only use the base cost), the plugin returns an error due to the amount being divided by zero:

[11-Jan-2023 22:24:33 UTC] PHP Fatal error: Uncaught DivisionByZeroError: Division by zero in /www/public/wp-content/plugins/mwb-bookings-for-woocommerce/common/class-mwb-bookings-for-woocommerce-common.php:266

I fixed by changing the code from

$unit = (int)($unit_price/$new_price);

to the following:

	if($unit_price != 0)
				{
				$unit = (int)($unit_price/$new_price);
			}
			else
			{
				$unit = 0;
			}

However it would be great if you can fix this in the next version so that my change won’t be overwritten by updating the plugin.

Thank you