Homepage: add licensed hero images

[eporter23]

For this ticket, we want to add an approved and licensed hero image to the homepage. These images were provided by Colin Bragg and are approved for us to use.

• Generate previews (screenshots are fine) of both of the following images: ATL skyline, medical researchers and add them to this ticket
• Add the final selected hero image to the homepage to replace the placeholder image

Note: at this time, we only want to add a single image, but a future ticket may involve adding functionality to randomly load an image from a set.

[CB987]

[CB987]

@eporter23 i can do full screenshots if that would be helpful.

[eporter23]

Thanks @CB987 - these both look good! Do you have a preference? Feel free to pick either one.

[CB987]

sounds good! thanks :)

[CB987]

PR#774