security/py-pyaff4: replace pyblake2 with pynacl

Import minimal upstream commit to switch from pyblake2 to pynacl.
This allows us to build run this port with python311:

https://github.com/aff4/pyaff4/commit/af2ce19c5a2ad61d68309a856ded93cee2901ea4

Full-blown update to latest version requires adding missing ports to tree.

PR: 277134
Approved by: antoine (maintainer)