docs: AGENTS.md: align commit subject format with SOF conventions #22942

Job	Run time
manifest-check	2m 47s
LP64-WIP	4m 44s
build-windows (mnfst, lnl)	9m 13s
build-windows (mnfst, tgl)	8m 35s
build-windows (mnfst, tgl-h)	9m 49s
build-windows (mnfst, mtl)	9m 59s
build-windows (mnfst, imx8 imx8x)	9m 31s
build-linux (mnfst, imx8 imx8x)	5m 3s
build-windows (mnfst, ptl)	11m 4s
build-linux (mnfst, wcl imx95)	7m 15s
build-linux (mnfst, tgl)	4m 8s
build-linux (-d, mnfst, lnl)	4m 38s
build-linux (mnfst, mtl)	5m 15s
build-linux (mnfst, tgl-h)	4m 29s
build-linux (mnfst, lnl)	4m 40s
build-windows (mnfst, imx8m imx8ulp)	9m 59s
build-linux (mnfst, ptl)	5m 54s
build-windows (-d, mnfst, lnl)	8m 45s
build-linux (mnfst, imx8m imx8ulp)	5m 32s
compare-linux-win	36s
	2h 11m 56s

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