Fixes this runtime error:
//-------------------------------------------------\\
|| runtime error: Cannot read null.status ||
|| proc name: handle heartbeat ||
|| (/mob/living/carbon/human/proc/handle_heartbeat)||
|| source file: life.dm,1648 ||
\\-------------------------------------------------//
This was caused by no sanity check to make sure that
internal_organs_by_name actually returned an organ, therefore it was
attempting to read a null variable, which causes a runtime error.
f3dd9d5e82