Add Athenian

[marnovo]

Thanks! Amazing list.

• Be sure to include a link to the company's main career page (e.g. beepi.com/careers/teams rather than jobs.lever.co/beepi).
• Maintain alphabetical order.
• For location add each city that they company is hiring software engineers for. Cities should be separated by a semicolon and be in alphabetical order.
• If the company hires remote employees include that under location as "Remote".
• It's alright for a single commit to have multiple companies.