Update setuptools to 46.3.0

[pyup-bot]

This PR updates setuptools from 46.2.0 to 46.3.0.

Changelog

46.3.0

-------

* 2089: Package index functionality no longer attempts to remove an md5 fragment from the index URL. This functionality, added for distribute 163 is no longer relevant.
* 2041: Preserve file modes during pkg files copying, but clear read only flag for target afterwards.
* 2105: Filter ``2to3`` deprecation warnings from ``TestDevelop.test_2to3_user_mode``.

Links

• PyPI: https://pypi.org/project/setuptools
• Changelog: https://pyup.io/changelogs/setuptools/
• Repo: https://github.com/pypa/setuptools

[duckinator]

bors r+

[bors]

Build succeeded:

• FreeBSD LANG:C.UTF-8 LC_ALL:C.UTF-8 PYTHON:3.7
• FreeBSD LANG:C.UTF-8 LC_ALL:C.UTF-8 PYTHON:3.8
• FreeBSD LANG:en_US.UTF-8 LC_ALL:en_US.UTF-8 PYTHON:3.6
• Lint
• Linux container:python:3.6-slim
• Linux container:python:3.7-slim
• Linux container:python:3.8-slim
• Linux_Py35
• macOS
• Windows container:python:3.6-windowsservercore-1809
• Windows container:python:3.7-windowsservercore-1809