Toolset update: VS 2022 17.0 Preview 5, Windows 11

[StephanTLavavej]

• azure-devops/create-vmss.ps1
  • Change the VM from D32ds_v4 (currently $0.6385/hour) to D32as_v4 (currently $0.4158/hour).
    • This has varied in the past, but we may as well use the cheaper one when we update. I've updated the toolset update checklist to link to Azure VM spot pricing.
  • Update the offer/sku to windows-11/win11-21h2-ent.
    • I've also updated the checklist accordingly. Thanks to @CaseyCarter for fixing Workaround ExceptionFlags change in NT #2265, unblocking Win11 validation.
    • This follows the casing that's printed by the query functions, although it appears to be case-insensitive.
• azure-devops/provision-image.ps1
  • Update to Python 3.10.0.
    • I'm not updating the README or the required Python version (still 3.9) as the VS Installer currently offers 3.9.5.
  • Remove Windows Driver Kit installation and bcdedit /set testsigning on, as investigation of kernel-mode testing has been unsuccessful.
    • This can still be investigated, but I believe it will be necessary to set up an independent Azure Pipelines CI for fast iteration.
• azure-pipelines.yml
  • Use the new pool.
• README.md
  • Mention Preview 5.
    • The CMake/Ninja versions are unchanged.
• tests/std/tests/P1502R1_standard_library_header_units/test.cpp
  • Remove a compiler workaround (thanks @cdacamar).
    • Technically this is unrelated to the toolset update and can be removed immediately, as we were skipping internal testing only.

---

I attempted to remove the EDG workaround in P1208R6_source_location:

STL/tests/std/tests/P1208R6_source_location/test.cpp

Line 4 in 8833270

#if defined(__cpp_consteval) && !defined(__EDG__) // TRANSITION, VSO-1285779

However, there are still failures, so further investigation is necessary.

[StephanTLavavej]

I'm mirroring this to an MSVC-internal PR; please notify me if any further changes are pushed.