Updates to the "notification email", specifically for the generation of the .ics file

It would be ideal for the notification email sent to the client to automatically insert the appointment scheduling into their calendar. (like tidycal).

I have personally made some modifications to the zoom plugin (/core/classes/class.bookingpress-zoom.php), adding parameters to complement the .ics file and I managed to effectively automate the insertion of the appointment in the calendar (tested in Google, Outlook, cpanel) and this improvement also allows the user to give a response to the scheduling coordinator. (here send a response to the coordinator's email).
View mod here: https://drive.google.com/drive/folders/1vfzej5SP6oUAYSAq8q8mt-oRp0IHEttA?usp=sharing
Greetings.