doc: Move remove_temp_files_after_crash to section for developer options
The main goal of this option is to allow inspecting temporary files for
debugging purposes, so moving the parameter there is natural.
Oversight in
cd91de0.
Reported-by: Justin Pryzby
Author: Euler Taveira
Discussion: https://postgr.es/m/
20210612004347.GP16435@telsasoft.com