[NEW] devel/py-unpaddedbase64: Unpadded Base64

Encode and decode Base64 without "=" padding.

RFC 4648 specifies that Base64 should be padded to a multiple of 4 bytes using
"=" characters. However this conveys no benefit so many protocols choose to use
Base64 without the "=" padding.

WWW: https://github.com/matrix-org/python-unpaddedbase64

PR: 205914
Submitted by: Brendan Molloy <brendan+freebsd@bbqsrc.net>