[perl #127226] QUOTE does not remove backslash with adverb :b

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# New Ticket Created by  Wenzel Peppmeyer 
# Please include the string:  [perl #127226]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=127226 >


my $x = 42; say Q:s:b{\$x}

# OUTPUT«\42␤»
# EXPECTED«42␤»