[v6.d REVIEW] Mark $/ interpolation fudge as OK to be 6.d-specced
[v6.d REVIEW] Mark $/ interpolation fudge as OK to be 6.d-specced

So we don't throw it out during release fudge purge, as it just
covers a bug and doesn't spec some new behaviour.
Orig: https://github.com/perl6/roast/commit/e25ff9945

perl6/roast,dogbert17/roast,dogbert17/roast