Allow lowercase letters in clan name (#877)

## Description:

Added possibility to use lowercase letters in clan name.
See issue #876 

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced
- [x] I understand that submitting code with bugs that could have been
caught through manual testing blocks releases and new features for all
contributors

## Please put your Discord username so you can be contacted if a bug or
regression is found:

theodoreleon.aetarax

src/core/game/Game.ts

@@ -334,7 +334,7 @@ export class PlayerInfo {
     if (!name.startsWith("[") || !name.includes("]")) {
       this.clan = null;
     } else {
-      const clanMatch = name.match(/^\[([A-Z]{2,5})\]/);
+      const clanMatch = name.match(/^\[([a-zA-Z]{2,5})\]/);
       this.clan = clanMatch ? clanMatch[1] : null;
     }
   }