rql #81865 Referenceable.get_type crashes if no solution given and variable linked using 'is IN(ET1,ET2...)' relation [validation pending]

prioritynormal
typebug
done in0.31.0
load0.100
load left0.000
closed by#1965eda264bd fix Referencable.get_type crash when no solution given and 'is IN(ET1, ET2..) is used. Closes #81865