update source code URLs following github redirects (#4025)

- some projects have been transferred to a new owner organization or the repository has been renamed
- rename EmbassyOS to StartOS

non-free.md

@@ -182,9 +182,9 @@
 - [Axigen](https://www.axigen.com/mail-server/free/) - Turnkey messaging solution for small & micro businesses, integration projects or test environments. `⊘ Proprietary` `Unknown`
 - [Cloudron](https://www.cloudron.io/) - Open-core software allowing you to effortlessly self-host web apps on your server. ([Demo](https://my.demo.cloudron.io/), [Source Code](https://git.cloudron.io/groups/cloudron)) `⊘ Proprietary` `Nodejs/Docker`
 - [Easypanel](https://easypanel.io) - Modern server control panel powered by Docker. `⊘ Proprietary` `Docker`
-- [EmbassyOS](https://start9.com) - Graphical Operating System for running self-hosted, open source services. ([Source Code](https://github.com/Start9Labs/embassy-os)) `⊘ Proprietary` `Rust`
 - [hMailServer](https://www.hmailserver.com) - Open-source e-mail server for Microsoft Windows. ([Source Code](https://github.com/hmailserver/hmailserver)) `⊘ Proprietary` `C++`
 - [Poste.io](https://poste.io) - Full-featured solution for your Email server. Native implementation of last anti-SPAM methods, webmail and easy administration included. Free tier available. ([Demo](https://poste.io/demo)) `⊘ Proprietary` `Unknown`
+- [StartOS](https://start9.com) -  Browser-based, graphical operating system for a personal server. ([Source Code](https://github.com/Start9Labs/start-os)) `⊘ Proprietary` `Rust`
 - [Umbrel](https://umbrel.com/) - A beautiful personal server OS for self-hosting. Install on a Raspberry Pi 4 or Ubuntu/Debian. ([Source Code](https://github.com/getumbrel/umbrel)) `⊘ Proprietary` `Nodejs/Docker`
 - [Unraid](https://www.unraid.net) `⚠` - Linux-based operating system designed to run on home media server setups. `⊘ Proprietary` `Other`