ci: add multi-artifact build #628

Job	Run time
Build and package cores	9m 6s
Split off zephyr_contrib	16s
Split off zephyr_unoq	14s
Split off zephyr	14s
Split off zephyr_main	13s
Test zephyr_main:opta	2m 39s
Test zephyr_main:giga	2m 42s
Test zephyr_contrib:frdm_mcxn947	2m 33s
Test zephyr_main:portentah7	2m 48s
Test zephyr_main:niclasense	2m 49s
Test zephyr_main:nano33ble	2m 49s
Test zephyr:unoq	2m 39s
Test zephyr_contrib:ek_ra8d1	2m 40s
Test zephyr_main:portentac33	2m 52s
Test zephyr_contrib:frdm_rw612	2m 38s
Collect logs	7s
Publish jsons	13s
Publish core	0s
verify-core	0s
cleanup-artifacts	6s
	37m 38s

Provide feedback