Drop UWP support

[MoeMod]

Currently luajit doesn't support uwp.
Moreover, it seems that nobody is still using uwp in 2021, including Microsoft's first-party softwares.

[Qiangong2]

I'd like to use the UWP version since I'm using a Surface 2 RT on win 10 arm

EDIT: the current build we do have, the cert is timestamped for last year. That means it won't work when installed unless you roll the clock back

[MoeMod]

done.
All 32bit version were dropped, and so was UWP armv7.