WEB: Update institutional sponsors list
Makes the lists consistent with the governance docs and adds d-fine

cc @MarcoGorelli Would you like to add gousto too?
> Makes the lists consistent with the governance docs and adds d-fine
> 
> cc @MarcoGorelli Would you like to add gousto too?

Thanks for the tag, will do when I get a chance!

EDIT: admittedly I've been struggling to make use of time to contribute, but hope to be able to do so regularly in the future thanks @phofl 