fix blog formatting on ios

[jaffee]

could also use some margin on android

see screenshot

[travisturner]

I propose we remove featured = "true" from content/blog/why-oci.md, and just have all blog posts use the same blog-card style. In my opinion it's not worth messing with css in order to support a wider "featured" post.

If someone objects and wants to support the featured post, I think we need to add a div around blog-card-featured in order to provide some outer bounds to use for constraining the content (currently those outer bounds are the entire width of the page).

[travisturner]

Ice-boxing this for now since our short-term solution is simply to avoid using the featured flag.