Completely Disable Newsletter Signups

[ChristianBingman]

The backend has been disabled which will just result in errors now. Let the user know that we are no longer accepting newsletter signups.

DoD:

• When the user Submits their join newsletter request it should prompt them to let them know that the event is closed
• The action should be consistent on both mobile and desktop
• Bonus points if the prompt looks nice and isn't just a built in alert

[goutham03062001]

Hello there, Is this issue still opened?

I would love to contribute to this project.