Summary:
we spawn the child processes with handle inheritance on. So they inherit the std handles.
The problem is that the job handle gets inherited too.
So the `JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE` doesn't get used since there are
open handles to the job in the children.

We then terminate the top level process which is `sh` but leaves the children around.

This explicitly disallows the inheritance of the job and events handle.

Test Plan: ./validate

Reviewers: austin, bgamari

Reviewed By: bgamari

Subscribers: thomie, #ghc_windows_task_force

Differential Revision: https://phabricator.haskell.org/D2895

GHC Trac Issues: #13004