python3-urllib3: upgrade 2.0.2 -> 2.0.3

https://github.com/urllib3/urllib3/blob/main/CHANGES.rst#203-2023-06-07



* Allowed alternative SSL libraries such as LibreSSL, while still issuing a
  warning as we cannot help users facing issues with implementations other
  than OpenSSL. (#3020)
* Deprecated URLs which don't have an explicit scheme (#2950)
* Fixed response decoding with Zstandard when compressed data is made of
  several frames. (#3008)
* Fixed assert_hostname=False to correctly skip hostname check. (#3051)

License-Update: Removed outdated reference to CONTRIBUTORS.txt

Signed-off-by: Tim Orling <tim.orling@konsulko.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>