[perl #131592] [ASYNC][REGRESSION] Piping from one Proc to another occasionally dies with "his process is not opened for write"

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# New Ticket Created by  Zoffix Znet 
# Please include the string:  [perl #131592]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=131592 >


    zoffix@VirtualBox~/CPANPRC/rakudo (nom)$ cat bar.p6
    for ^4000 {
        my $p = run(:out, :bin, 'ls'); run(:in($p.out), 'true')
    }
    zoffix@VirtualBox~/CPANPRC/rakudo (nom)$ ./perl6 bar.p6 
    Unhandled exception in code scheduled on thread 12
    Tried to get the result of a broken Promise

    Original exception:
        This process is not opened for write

    zoffix@VirtualBox~/CPANPRC/rakudo (nom)$