Update p5-Proc-Simple to 1.30.

Changes from previous:
----------------------
  From 1.29:
	     [RT 69782] Zefram reported race condition in t/sh-c.t,
	     fixed by adding polling loop.

	     Found that kill(-sig, pid) sometimes fails with
	     'process id not found' although a previous kill(0, pid)
	     succeeded. This is a race condition condition caused
	     by a newly forked child that hasn't called setsid() yet
	     and therefore its new process group id doesn't exist yet,
	     although the child responds to poll(). kill() now
	     deals with this case.
  From 1.28:
	     [RT 69103] Typo fix by Salvatore Bonaccorso
	     Added support for processes called via 'sh -c' by
	     system() (see "Shell Processes" note in the manpage).
  From 1.27:
	     [RT 62802] Pod fix by Salvatore Bonaccorso
	     [RT 63833] Applied patch to stop reaping PIDs of
	       no longer existing processes (submitted by perlbotics).
	     Added licensizer
	     [RT 63833] (second part) Added cleanup() class method
	     to delete timing data of reaped processes, avoiding
	     infinite memory growth on long-running processes

  From 1.26: [RT 62285] Pod fix for redirect_output()
	     Fixed github link


(hiramatsu)