scripts: delete module_size accumulator before each west build #23216

Job	Run time
manifest-check	3m 27s
LP64-WIP	4m 3s
build-windows (mnfst, ptl)	11m 1s
build-windows (mnfst, imx8 imx8x)	10m 4s
build-windows (-d, mnfst, lnl)	9m 40s
build-linux (mnfst, lnl)	4m 20s
build-windows (mnfst, imx8m imx8ulp)	10m 2s
build-windows (mnfst, tgl-h)	10m 25s
build-linux (mnfst, imx8 imx8x)	5m 37s
build-linux (mnfst, mtl)	4m 43s
build-linux (mnfst, tgl-h)	4m 58s
build-windows (mnfst, mtl)	9m 0s
build-linux (mnfst, imx8m imx8ulp)	5m 0s
build-linux (-d, mnfst, lnl)	5m 10s
build-linux (mnfst, wcl imx95)	7m 19s
build-windows (mnfst, lnl)	9m 28s
build-windows (mnfst, tgl)	8m 42s
build-linux (mnfst, tgl)	4m 1s
build-linux (mnfst, ptl)	5m 46s
compare-linux-win	33s
	2h 13m 19s

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