Set the name of ics files downloaded from our website

[alsahawneh]

When a user wants to download an ics file for a specific JOSA event, the name of the downloaded file is always JOSAEvent.ics.

For many reasons, the best practice here is to set the name of that file to be the same as the event's name. For example, if our users want to download the Hacktoberfest Amman ics file, the name of the downloaded file should be HacktoberfestAmman.ics instead of JOSAEvent.ics.