ci: add multi-artifact build #637

Job	Run time
Build and package cores	8m 52s
Split off zephyr_contrib	15s
Split off zephyr_main	9s
Split off zephyr_unoq	6s
Split off zephyr	10s
Test zephyr_main:niclasense	2m 46s
Test zephyr_main:giga	2m 43s
Test zephyr_contrib:ek_ra8d1	2m 33s
Test zephyr:unoq	2m 33s
Test zephyr_main:nano33ble	2m 49s
Test zephyr_main:portentah7	2m 47s
Test zephyr_main:portentac33	2m 52s
Test zephyr_main:opta	2m 51s
Test zephyr_contrib:frdm_mcxn947	2m 36s
Test zephyr_contrib:frdm_rw612	2m 36s
Collect logs	8s
Publish jsons	15s
verify-core	0s
Publish core	0s
cleanup-artifacts	4s
	37m 5s

Provide feedback