meta: clarify EoL platform support
Use stronger wording about EoL platforms. Make it clear they can be removed at any time, as should happen with Windows 7/2008R2 next year when it becomes EoL.
cc @nodejs/build
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
documentation is changed or added -
commit message follows commit guidelines