convert pool Madoka - Lonely Mami -> left_out

BUR #60284 is pending approval.

convert pool:4220 -> left_out

Moving from forum #440051 and forum #440161.

lonely is too broad. left out is a more specific tag for this, though I don't know if left out should imply lonely.

Lonely suggests the character has negative feelings from being alone. A person being left out might feel sad, but they could also be indifferent or even happy. So no, I don't think left out should imply lonely.