telemetry: fix lock leak on slot alloc failure #22870

Job	Run time
build-windows (mnfst, lnl)	9m 44s
LP64-WIP	4m 12s
build-windows (mnfst, ptl)	10m 6s
build-windows (mnfst, mtl)	8m 29s
build-windows (mnfst, tgl-h)	8m 57s
build-windows (mnfst, imx8 imx8x)	10m 3s
build-windows (-d, mnfst, lnl)	8m 22s
build-linux (mnfst, tgl-h)	4m 30s
build-linux (mnfst, ptl)	6m 4s
build-linux (mnfst, imx8m imx8ulp)	5m 5s
build-linux (mnfst, tgl)	4m 23s
build-windows (mnfst, imx8m imx8ulp)	10m 25s
manifest-check	2m 48s
build-linux (-d, mnfst, lnl)	4m 57s
build-windows (mnfst, tgl)	9m 26s
build-linux (mnfst, lnl)	4m 46s
build-linux (mnfst, mtl)	5m 2s
build-linux (mnfst, wcl imx95)	7m 13s
build-linux (mnfst, imx8 imx8x)	5m 41s
compare-linux-win	32s
	2h 10m 45s

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