Ensure `close` is called on the response body no matter what
Ensure `close` is called on the response body no matter what

Another fallout from https://github.com/puma/puma/pull/2809 is that
in some cases the `res_body.close` wasn't called because some previous code
raised.

For Rails apps it means CurrentAttributes and a few other important
states aren't reset properly.

This is being improved on the Rails side too, but I believe it would
be good to harden this on the puma side as well.

eileencodes/puma,eileencodes/puma,puma/puma,eileencodes/puma,puma/puma,puma/puma,eileencodes/puma,puma/puma