Update the opengraph image for social media previews

[ryelle]

Currently, the image used on social media is this:

We should update this before the redesign rolls out. cc @WordPress/meta-design

[jasmussen]

Two quick options:

The syntax of the latter is one we can hopefully also use with the theme and plugin directories.

PNG exports of those two.

Archive.zip

[ryelle]

I like the second one, I think it will have more context for someone just scrolling by on social media.