API Annotations: parens anns discarded for `(*)` operator

The patch from ​https://phabricator.haskell.org/D4865 introduces

go _ (HsParTy _ (dL->L l (HsStarTy _ isUni))) acc ann fix
  = do { warnStarBndr l
       ; let name = mkOccName tcClsName (if isUni then "★" else "*")
       ; return (cL l (Unqual name), acc, fix, ann) }

which discards the parens annotations belonging to the HsParTy.

Closes #16265 (closed)