Fix category zero-k syntax

Signed-off-by: Nathan Rew <nrew225@gmail.com>

README.md

@@ -854,7 +854,7 @@ _Games, game servers and control panels._
 - [Teeworlds](https://www.teeworlds.com) - Open source 2D retro multiplayer shooter. ([Source Code](https://github.com/teeworlds/teeworlds)) `BSD-3-Clause/Other` `C++`
 - [TournamentMango](https://github.com/seiyria/tournamentmango) - TournamentMango is an open source tournament bracket and user management system. You can build an archive of players and keep track of all their scores over time as well as their regular characters, games, and aliases. `MIT` `Javascript`
 - [The Battle for Wesnoth](https://github.com/wesnoth/wesnoth) - The Battle for Wesnoth is an Open Source, turn-based tactical strategy game with a high fantasy theme, featuring both singleplayer and online/hotseat multiplayer combat. `GPL-2.0` `C++`
-- [Zero-K](https://zero-k.info/) - Open Source on Springrts engine. Zero-K is a traditional real time strategy game with a focus on player creativity through terrain manipulation, physics, and a large roster of unique units - all while being balanced to support competitive play. ([Source code](https://github.com/ZeroK-RTS/Zero-K)) `GPL-2.0` `Lua`
+- [Zero-K](https://zero-k.info/) - Open Source on Springrts engine. Zero-K is a traditional real time strategy game with a focus on player creativity through terrain manipulation, physics, and a large roster of unique units - all while being balanced to support competitive play. ([Source Code](https://github.com/ZeroK-RTS/Zero-K)) `GPL-2.0` `Lua`
 
 ## Gateways and terminal sharing