py-rpyc: update to version 4.0.2

Release rpyc 4.0.2
- fix default hostname for ipv6 in rpyc_classic.py (#277)
- fix ThreadPoolServer not working

Release rpyc 4.0.1
- fix ValueError during install due to absolute PATH in SOURCES.txt (`#276`_)

Release rpyc 4.0.0
This release brings a few minor backward incompatibilities, so be sure to read
on before upgrading. However, fear not: the ones that are most likely relevant
to you have a relatively simple migration path.

(khorben)