gamemode cooldown is causing lowpop rounds to disproportionately be survival and kessler

[hivehum]

Description

i dont play lowpop often so i havent experienced this personally but it appears from people talking in discord that we essentially Only Ever roll kessler on sub 20 population rounds

Additional context
if i were in charge of fixing this i would add a baby mode gamemode to secret that is like, calm events scheduler and side antags, and make it only able to roll under 20 player population. but im sure there are more elegant solutions

[TGRCdev]

I thought greenshift was included in the secret pool, but turns out I'm totally wrong.

We could definitely add an additional game preset with a low max player cap and reduced events.

[hivehum]

resolved by #872