Struct migrations insert #:extra-constructor-name unnecessarily

[jackfirth]

See racket/scribble#295 for context. Fixing this is tricky, because it requires knowing that all uses of the make- constructor can be rewritten. This requires first making a pass over the module to look for define-struct forms, then making a pass to look for usages of their constructors, then finally making a third pass to look for define-struct forms whose constructors can all be rewritten. This would require significantly reworking the refactoring rule API and the implementation of the source code analysis phase. It seems like it would enable producing far more useful suggestions, so it's worth exploring.

[sorawee]

Also, in presence of struct-out or all-defined-out, you can't drop #:extra-constructor-name.