[GH-917] - Deathmatch mode

[tvillegas98]

Warning

Merge alongside https://github.com/lambdaclass/champions_of_mirra/pull/2230

Motivation

Add a new game mode based on the deathmatch concept. All against all mode where the player with most kills wins the match.

Closes #917

Summary of changes

• Added a new matchmaking for deathmatch mode
• Added a respawn feature only enabled for deathmatch mode
• Added a new win condition only enabled for deathmatch mode
• Send the gamemode to the client

How to test it?

• Open the browser client and play a game in the deathmatch mode. If you want, you can print the winner in apps/arena/lib/arena/game_updater.ex:337 and check that it is correct

Checklist

• Tested the changes locally.
• Reviewed the changes on GitHub, line by line.
• This change requires new documentation.
  • Documentation has been added/updated.

[tvillegas98]

We have a matchmaking file for each game mode

[tvillegas98]

all changes were done in chore: requested changes