raytracer: Use `Vol<&[TracingCubeData]>` in `SurfaceIter`. #216

Job	Run time
no_std	43s
build (ubuntu, stable, locked, true)	30m 58s
miri	1m 33s
build (windows, stable, locked, false)	34m 16s
build (macos, stable, locked, false)	20m 33s
build (ubuntu, nightly, locked, false)	22m 45s
build (ubuntu, beta, locked, false)	8m 37s
build (ubuntu, stable, latest, false)	14m 1s
build (ubuntu, stable, minimal, false)	25m 24s
deploy	6s
fuzz	16m 1s
	2h 54m 57s

Provide feedback