remove lines between docstring and symbol

[johnnychen94]

Empty lines are not allowed; otherwise ?BoundaryFill gives nothing useful:

help?> BoundaryFill
search: BoundaryFill

  No documentation found.

  ImageDraw.BoundaryFill is of type UnionAll.

  Summary
  ≡≡≡≡≡≡≡≡≡

  struct UnionAll <: Type{T}

  Fields
  ≡≡≡≡≡≡≡≡

  var  :: TypeVar
  body :: Any

  Supertype Hierarchy
  ≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡

  UnionAll <: Type{T} <: Any

This PR fixes the docstring issue by removing those unnecessary empty lines.

cc: @ashwani-rathee