contrib: install the arm64 compiler tools in the Windows dependency script This lets us build arm64 wheels on Windows. We should update from VS 2017 to VS 2019, but that can wait until there's a clean Windows system available. There's a little bit of handwaving here because I originally installed some packages on the CI system by checking boxes in the GUI installer to get arm64 support, since I didn't know the name(s) of the things needed. Exporting the configuration from the GUI installer showed the list of things present, and then I was able to run `vs_buildtools.exe` on another system that previously had this dependency script run a few years ago, with just this new arg. That allowed the wheels to be built (the process failed on this second system prior to this). The only difference between the CI system configuration prior to installing arm64 stuff and this second system after, is the second system has the WinXP support component. Surprisingly, the arm64 WDK and arm64 CRT or Universal CRT doesn't seem to be required.