[perl #131590] .cando fails to locate candidates with native parameters

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# New Ticket Created by  Zoffix Znet 
# Please include the string:  [perl #131590]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=131590 >


Using .cando, the method with native str param doesn't get found, even when 
using native str in the Capture:

    <Zoffix__> m: class Foo { method x(str $y) { say "here" } }; dd 
Foo.^lookup('x').cando: \(Foo, my str $ = 'x')
    <camelia> rakudo-moar 369f25: OUTPUT: «()␤»
    <Zoffix__> m: class Foo { method x(str $y) { say "here" } }; dd 
Foo.^lookup('x').cando: \(Foo, 'x')
    <camelia> rakudo-moar 369f25: OUTPUT: «()␤»

Yet it can be called with and without using name str arg:

    <Zoffix__> m: class Foo { method x($y) { say "here" } }; dd Foo.x: 'x'
    <camelia> rakudo-moar 369f25: OUTPUT: «here␤Bool::True␤»
    <Zoffix__> m: class Foo { method x(str $y) { say "here" } }; dd Foo.x: 'x'
    <camelia> rakudo-moar 369f25: OUTPUT: «here␤Bool::True␤»
    <Zoffix__> m: class Foo { method x(str $y) { say "here" } }; dd Foo.x: my 
str $ = 'x'
    <camelia> rakudo-moar 369f25: OUTPUT: «here␤Bool::True␤»