flip bot_primary_fireballmooth boolean so bots are able to fire fireball alt fire randomly

Previously when it was 1 it was assigned 1 and when it was 0 it was assigned 0 and values never got mixed. Now 1 gives 0 and 0 gives 1 on a random roll success which makes bots switch between firing modes.

git blame pointed to @Mario (from 2016 😅) so I'll ping just to make sure that this was an innocent mistake and not a decision to lock bots into primary fire.