fix: [stix2 export] Make Relationship objects happy with relationship types
fix: [stix2 export] Make Relationship objects happy with relationship types

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