jenkins: remove v16 from VersionSelectorScript

[targos]

No description provided.

[richardlau]

It's written down that we keep stuff around for 6 months after a release line goes End-of-Life before removing.

build/README.md

Lines 294 to 296 in 2e7c763

	The Build WG will keep build configuration required for a release line for 6
	months after the release goes End-of-Life, in case further build or test runs
	are required. After that the configuration will be removed.

FWIW I can only remember one time when we decided to do an additional release after End-of-Life, which IIRC was within the month after the End-of-Life.

[mhdawson]

I would be good to keep this around a bit longer if possible. I don't think it hurts anything, right?

[targos]

That's why I made this a draft. I'll come back to it in 6 months.

[targos]

Ready for a new review.

[StefanStojanovic]

LGTM, Removing VS2015 and VS2017 from compilation jobs is highly optional.

EDIT: I was thinking about maybe removing the vs2015 and vs2017 compilation configurations completely, but that is not very urgent. I may open a follow-up PR for that at some point.