[perl #130213] [LTA] but mixins don't complain about sink context

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# New Ticket Created by  Wenzel Peppmeyer 
# Please include the string:  [perl #130213]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=130213 >


role R1 { method m {} }; role R2 { method m {} }; my $a but R1,R2;

# R2 ends up in sink context without any complaint. That may become a
# hairpulling trap for many users.