os: test overlapped pipes deadlines on Windows

NewFile recently added support for overlapped I/O on Windows,
which allows us to set deadlines on them, but the test coverage for
this new feature is not exhaustive.

Modify the existing pipe deadline tests to also exercise named
overlapped pipes.

Updates #19098.

Cq-Include-Trybots: luci.golang.try:gotip-windows-amd64-race,gotip-windows-amd64-longtest,gotip-windows-arm64
Change-Id: I86d284d9fb054c24959045a922cf84feeda5b5f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/668095
Reviewed-by: Alex Brainman <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Carlos Amedee <[email protected]>
Reviewed-by: Junyang Shao <[email protected]>

Author: qmuntal