Clear signature before parsing block
Clear signature before parsing block

If we do not do this then the block takes on the signature of the
enclosing routine, leaking %*SIG_INFO<returns> into the block and
causing the block to return any declared return value of the enclosing
sub.

See also: https://github.com/rakudo/rakudo/issues/3070.

salortiz/rakudo,tbrowder/rakudo,nbrown/rakudo,softmoth/rakudo,rakudo/rakudo,labster/rakudo,tony-o/rakudo,softmoth/rakudo,labster/rakudo,tbrowder/rakudo,tony-o/rakudo,nbrown/rakudo,MasterDuke17/rakudo,nbrown/rakudo,salortiz/rakudo,rakudo/rakudo,softmoth/rakudo,MasterDuke17/rakudo,labster/rakudo,labster/rakudo,tony-o/rakudo,tbrowder/rakudo,MasterDuke17/rakudo,rakudo/rakudo,nbrown/rakudo,tony-o/rakudo,nbrown/rakudo,tbrowder/rakudo,salortiz/rakudo,rakudo/rakudo,MasterDuke17/rakudo,MasterDuke17/rakudo,rakudo/rakudo,tbrowder/rakudo,labster/rakudo,salortiz/rakudo,softmoth/rakudo,softmoth/rakudo,tony-o/rakudo,tbrowder/rakudo,salortiz/rakudo,tony-o/rakudo,MasterDuke17/rakudo,salortiz/rakudo,labster/rakudo,nbrown/rakudo,rakudo/rakudo