Suspend process execution with SIGSTOP preemptively checking
whether PID has been reused. On Windows this has the effect of
suspending all process threads.
# NOT RUN {px <- processx::process$new("sleep", "10")
p <- ps_handle(px$get_pid())
p
ps_suspend(p)
ps_status(p)
ps_resume(p)
ps_status(p)
ps_kill(p)
# }