versions.json: set version to 2.12.99 #19570

Job	Run time
build-windows (imx8 imx8x imx8m imx8ulp)	8m 9s
build-linux (mnfst, imx8 imx8x imx8m imx8ulp)	6m 24s
build-windows (mtl)	5m 34s
manifest-check	54s
LP64-WIP	4m 26s
build-windows (tgl tgl-h)	6m 55s
build-linux (mnfst, mtl)	4m 41s
build-linux (mnfst, lnl)	4m 35s
build-windows (-d, mtl)	6m 4s
build-linux (mnfst, ptl)	4m 41s
build-linux (mnfst, tgl tgl-h)	5m 23s
build-linux (zmain, imx8 imx8x imx8m imx8ulp)	6m 18s
build-linux (zmain, mtl)	4m 30s
build-linux (zmain, lnl)	4m 26s
build-linux (zmain, ptl)	4m 19s
build-linux (zmain, tgl tgl-h)	5m 24s
build-linux (-d, mnfst, mtl)	4m 39s
build-linux (mnfst, --all)	13m 52s
compare-linux-win	25s
	1h 41m 39s

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