new: [sync] Block pulled events from being saved if they contain no attributes/objects
new: [sync] Block pulled events from being saved if they contain no attributes/objects

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