[landing] redesign keyserver company section on keyserver page

Summary:
This diff updates the UI for the last section of the keyserver page to match the figma designs. Subsequent diffs will address the other sections. Here is the design for refernece:

Depends on D8132

Test Plan:
Please view the demo videos/screenshot

Desktop/Responsive:

Tablet:

Mobile:

Reviewers: atul, kamil

Reviewed By: kamil

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D8165