pgsql: Re-enable autoruns for cmd.exe on Windows

Re-enable autoruns for cmd.exe on Windows

This acts as a revert of b83747a8a65b and 9886744a361b.  As pointed out
by Noah, HEAD and REL_17_STABLE are in a weird state where the code
paths adding /D would limit the spawn of child processes, but we still
have code paths where the spawn of more than one child process(es) would
be possible.

Let's remove these /D switches for now, to bring back the code into a
state consistent with how autorun is configured on a Windows host.

Reported-by: Noah Misch
Discussion: https://postgr.es/m/20240630021211.f3.nmisch@google.com
Backpatch-through: 17

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/74b8e6a698025fbea5a5e22ea09d07d97188c1d6

Modified Files
--------------
src/bin/pg_ctl/pg_ctl.c       | 4 ++--
src/test/regress/pg_regress.c | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)