Add DPG badge to the footer

[tm-miha]

We made it with Interfacer into DPG!
We can add the DPG badge to the IF footer and link it to the DPGA registry https://app.digitalpublicgoods.net/a/10892

Logos here:
https://digitalpublicgoods.net/DPGA_Brand-Guide.pdf

Badge here:
https://s3.amazonaws.com/dpg-website/wp-content/uploads/2021/05/28162832/dpg1.svg

Digital Public Goods Alliance Registry number for IF:
https://app.digitalpublicgoods.net/a/10892