wip: [stix2 import] Process observables import reworked
wip: [stix2 import] Process observables import reworked

MISP/MISP,SteveClement/MISP,SteveClement/MISP,MISP/MISP,MISP/MISP,SteveClement/MISP,SteveClement/MISP,SteveClement/MISP,MISP/MISP,MISP/MISP