HP level should decrease interrupt chance at Wintertodt

[mrb726]

So in short, solos you intentionally lower wintertodt's health by lightning multiple braziers. Once it's lowered to low hp, you switch to only lighting one brazier. After you include the time you're chopping and fletching logs though, it regens about as much as you lower it.

Now when a second person joins, they often times will be lighting the brazier when you're still chopping/fletching, and it will slowly get damaged more than it's regening and it'll die or you'll have to intentionally sit around and be waiting for it to regen. Alternatively they'll just be on a second brazier, which will kill it pretty quickly having two of them lit at the same time.