[io grant] Test IO::CatHandle.getc
[io grant] Test IO::CatHandle.getc

1 TODOed test due to IO::Handle.getc bug:
https://rt.perl.org/Ticket/Display.html?id=131365

dogbert17/roast,bitrauser/roast,bitrauser/roast,dogbert17/roast,perl6/roast