Enable PGO tests on `windows-gnu`

[mati865]

#61080 enabled profiler for windows-gnu dist jobs and it seems to work.
I didn't know if CI has enough budget to enable it for tests as well so it was left for now but it should be enabled in the future.

Related issue: #59637

@michaelwoerister you might want to add this issue to #59913

@rustbot modify labels: +O-windows-gnu +T-infra

[mati865]

@rustbot modify labels: +O-windows-gnu +T-infra

[michaelwoerister]

I'd love it if we ran tests here too. Compiling the profiler runtime shouldn't be a big deal, buildtime-wise. I don't think it should block stabilization though.

[michaelwoerister]

cc @rust-lang/infra

[mati865]

Six years have passed, and the GNU toolchain still cannot build LLVM sanitizers. I doubt it ever will, so keeping this open doesn't seem sensible to me.
For MinGW-w64 based toolchains that support profilers and sanitizers, use windows-gnullvm targets.