chg: [internal] Delete unused method Attribute::saveAndEncryptAttribute
chg: [internal] Delete unused method Attribute::saveAndEncryptAttribute

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