Panic upon solitary quantifiers in regexes.
Panic upon solitary quantifiers in regexes.

The error case here is unable to construct an AST that will not blow
up in interesting ways later on in compilation, so we need to abort.
Fixes RT #130812, where the `sorry` rather than `panic` led to an
internal error because of follow-up operations on a malformed AST.

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