fix: [stix2 import] Fixed labels parsing & custom properties parsing
fix: [stix2 import] Fixed labels parsing & custom properties parsing

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