Additional tests in CI

[Jeremy Drake]

On Thu, 29 May 2025, Jon Turney wrote:

> Please, feel free to push additional tests there, (ideally after or
> simultaneously with a fix, so we don't get failures :))
>
> (or to suggest additional regression tests, if you don't have push rights)

Would that be as user cygwin@cygwin.com like cygwin-packages or as a
sourceware user like newlib-cygwin?  Do push rights to that come along
with push rights to newlib-cygwin?