python3: Update to 3.8.4, refresh/rework patches, backport patches

python3: Update to 3.8.4, refresh/rework patches, backport patches

This version includes fixes for:
* CVE-2020-14422: Hash collisions in IPv4Interface and IPv6Interface
* CVE-2020-15523: Python uses invalid DLL path after calling Py_SetPath
  on Windows

This version also includes support for OpenSSL 1.1.x builds that use
'no-deprecated' and '--api=1.1.0'[1], and so this removes the previous
OpenSSL-related patches.

This also backports fixes for security issues, including:
* CVE-2019-20907: Infinite loop in the tarfile module

This also updates the setuptools and pip packages to 47.1.0 and 20.1.1,
respectively.

[1]: https://github.com/python/cpython/pull/20566

Signed-off-by: Jeffery To <jeffery.to@gmail.com>