Building binary out of a subfolder

[cBournhonesque]

My team's game https://github.com/cBournhonesque/jam5 started from the template, but i had a lot of CI issues because our binary is built in the client folder.
I made a couple of changes to the CI to account for that, but it took me a long time to figure them out

Maybe there could be an ENV in the release.yaml that specifies the folder containing the game

[benfrankel]

Agreed that we should be providing this functionality behind an env variable. It's a major pain for users otherwise.

[benfrankel]

This is a duplicate of #194 actually.