fix: [stix export] Fixed child-pid attributes export that used to make the process object export fail
fix: [stix export] Fixed child-pid attributes export that used to make the process object export fail

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