Make reproduction CI test

[GuardianDll]

Summary

None

Purpose of change

There is no reason to hold back #76266 because i can't get what's wrong with the test i made

Describe the solution

Move the test from #76266 here

Testing

Additional context

Relies on #76266 for obv reasons, and relies on #76264 because otherwise i'd need to do shenanigans with unloading and loading monster back

[mqrause]

try_reproduce doesn't actually spawn monsters, it just tells the map to spawn them on the next occasion. So calling spawn_monsters on the map after try_reproduce should probably fix it.

[GuardianDll]

what about failing monsters_spawn_egg_itemgroups? this one spawns items, and... oh right, it's probably because spawn_items() works only outside of bub. How would i do it then? run try_reproduce(), then teleport avatar afar, and then teleport them back?

[mqrause]

I was looking at this run, which didn't fail for eggs.

[GuardianDll]

🤔
i'll come back to this PR when previous two will be merged