Add meta description and preview/meta image

[torotimes]

[torotimes]

https://github.com/working-group-two/wgtwo.com/blob/main/website/docusaurus.config.js

[torotimes]

Here's a proposed meta description for now:

We help mobile operators innovate at scale, reduce cost and dive into new revenue streams - by building a mobile core network from the ground up and delivering it as-a-service.