[perl #132128] [LTA] .new of subclasses of Int returns an Int

[via RT]

# New Ticket Created by  Zoffix Znet 
# Please include the string:  [perl #132128]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=132128 >


    m: class Foo is Int {};  my Foo $x .= new: 42; say $x; say $x.WHAT;
    rakudo-moar bb4579: OUTPUT: «Type check failed in assignment to $x; 
expected Foo but got Int (42)␤  in block <unit> at <tmp> line 1␤␤»

This was broken by the fix to make it correctly handle >64bit ints, but 
apparently there are even articles that show how to subclass Ints: 
https://irclog.perlgeek.de/perl6/2017-09-19#i_15187511

The likely fix would be Int.new changed to this:

    method new (Int() \value) {
        nqp::p6bindattrinvres(self.bless, Int, q|$!value|, 
nqp::getattr(nqp::decont(value), Int, q|$!value|))
    }

But that currently segfaults: https://rt.perl.org/Ticket/Display.html?id=132126