[perl #111646] &infix<~> reports an arity of 2 even though it accepts 2

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# New Ticket Created by  Moritz Lenz 
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09:38 < moritz> nom: say &infix:<~>.arity
09:38 <+p6eval> rakudo 4235df: OUTPUT«1␤»
09:38 < moritz> nom: say &infix:<~>.count
09:38 <+p6eval> rakudo 4235df: OUTPUT«1␤»
09:38 < moritz> ah, that's wrong
09:39 < moritz> nom: say &infix:<~>(2, 3)
09:39 <+p6eval> rakudo 4235df: OUTPUT«23␤»

This leads to @list.reduce(&infix:<~>) failing, because reduce thinks it 
got an unary operator.