[Backport release-3_40] [raster calculator] Fix output CRS not taken from first raster entry, safeguard from crash #36522

Job	Run time
build (22.04, 5, true, OFF, ON, ON, ON, ON, OFF, OFF, OFF, OFF, ON, false)	1h 44m 41s
build (39, 6, true, ON, OFF, ON, ON, OFF, OFF, ON, ON, ON, OFF, false)	3h 8m 12s
clang-tidy (22.04, 5)	7m 18s
Run tests (5, ALL_BUT_PROVIDERS)	31m 21s
Run tests (5, POSTGRES)	8m 7s
Run tests (5, HANA)	19m 35s
Run tests (6, ALL_BUT_PROVIDERS)	37m 38s
Run tests (5, ORACLE, 22.04, binary-for-oracle)	7m 55s
	6h 44m 47s

Provide feedback