new: Refactor of the warning message for the add attribute view
new: Refactor of the warning message for the add attribute view

Rafiot/MISP,devnull-/MISP,SteveClement/MISP,MISP/MISP,FloatingGhost/MISP,devnull-/MISP,MISP/MISP,devnull-/MISP,FloatingGhost/MISP,Rafiot/MISP,FloatingGhost/MISP,MISP/MISP,FloatingGhost/MISP,devnull-/MISP,FIRSTdotorg/MISP,SteveClement/MISP,MISP/MISP,FIRSTdotorg/MISP,Rafiot/MISP,SteveClement/MISP,Rafiot/MISP,FIRSTdotorg/MISP,MISP/MISP,FIRSTdotorg/MISP,SteveClement/MISP,SteveClement/MISP