make 'description' field required + add helper prompt underneath 'description' field

[aliyakernel]

too many times this block when fellows created events, they have left the description field blank, causing people to rely on the cal event that has the location info, however someone deciding if they'd like to go can't see that information yet without RSVPing & accepting cal invite, causing loss of information / not enough to decide if they'd like to go (NYC + Denver events are the ones immediately coming to mind).

can we make the description field required please? and provide this prompt underneath description field to help proposers:

"What is your event about? If it's an IRL event, where will it be located? What is the address? While this information shows in the calendar event, a person deciding if they'd like to RSVP can't see that information yet. Please help readers decide if they'd like to attend by providing more details here."