Finalize fix for Rational.ceiling/.floor
Finalize fix for Rational.ceiling/.floor

The original fix[^1] is good; the <4/2> Rat gets created during
addition of two Rats and it's not reduced there for performance reasons.

So keep the reduction in .ceiling and toss it from .floor as it's not
needed there.

[1] https://github.com/rakudo/rakudo/commit/6372417035b959f971a58490101

MasterDuke17/rakudo,labster/rakudo,usev6/rakudo,nbrown/rakudo,MasterDuke17/rakudo,salortiz/rakudo,lucasbuchala/rakudo,MasterDuke17/rakudo,nbrown/rakudo,sjn/rakudo,lucasbuchala/rakudo,awwaiid/rakudo,labster/rakudo,labster/rakudo,Gnouc/rakudo,softmoth/rakudo,Gnouc/rakudo,tbrowder/rakudo,Gnouc/rakudo,sjn/rakudo,usev6/rakudo,usev6/rakudo,sjn/rakudo,labster/rakudo,usev6/rakudo,raydiak/rakudo,raydiak/rakudo,awwaiid/rakudo,raydiak/rakudo,Gnouc/rakudo,softmoth/rakudo,tony-o/rakudo,salortiz/rakudo,salortiz/rakudo,rakudo/rakudo,salortiz/rakudo,softmoth/rakudo,nbrown/rakudo,jonathanstowe/rakudo,nbrown/rakudo,MasterDuke17/rakudo,tbrowder/rakudo,raydiak/rakudo,jonathanstowe/rakudo,awwaiid/rakudo,nbrown/rakudo,tbrowder/rakudo,tony-o/rakudo,nbrown/rakudo,labster/rakudo,softmoth/rakudo,awwaiid/rakudo,MasterDuke17/rakudo,tony-o/rakudo,tony-o/rakudo,tbrowder/rakudo,sjn/rakudo,rakudo/rakudo,Gnouc/rakudo,usev6/rakudo,lucasbuchala/rakudo,tbrowder/rakudo,tony-o/rakudo,awwaiid/rakudo,rakudo/rakudo,jonathanstowe/rakudo,lucasbuchala/rakudo,sjn/rakudo,tbrowder/rakudo,jonathanstowe/rakudo,rakudo/rakudo,softmoth/rakudo,rakudo/rakudo,rakudo/rakudo,jonathanstowe/rakudo,lucasbuchala/rakudo,salortiz/rakudo,MasterDuke17/rakudo,labster/rakudo,salortiz/rakudo,Gnouc/rakudo,tony-o/rakudo