Option to remove unsupported annotations from `numpy.ndarray` and `List` in stubgen

Feature

Command-line arguments for stubgen that when enabled will remove unsupported annotations from numpy.ndarray and List
like numpy.ndarray[numpy.float32[3,1]] and List[float[3]] which pybind11 outputs.

FYI: This feature has been implemented for numpy.ndarray in pybind11-stubgen.

Pitch

The stubs generated from extensions made with pybind11 using mypy.stubs are invalid when Eigen types or std::array are used in the interface.

As an example, this output from stubgen,

    def as_numpy(self) -> numpy.ndarray[numpy.float32[3,1]]: ...

will give the following errors when used together with Mypy:

error: Bad number of arguments for type alias, expected: 0, given: 2
error: "ndarray" expects 2 type arguments, but 1 given
error: Invalid type: try using Literal[2] instead?
error: Invalid type: try using Literal[1] instead?

And this

def split(axis_aligned_bounding_box: AxisAlignedBoundingBox, max_extents: List[float[3]]) -> List[AxisAlignedBoundingBox]: ...

will give these errors:

error: "float" expects no type arguments, but 1 given
error: Invalid type: try using Literal[3] instead?

stubgen のコマンドラインエントリポイントから開始し、numpy.ndarray[...] や List[...] などのアノテーションがどのように出力されるかを追跡します。サポートされていないアノテーションを削除するオプションを追加し、生成されたスタブで説明されている mypy エラーが発生しなくなることを確認します。