Update python-os-api-ref to version 2.3.0 / rev 14 via SR 977080
https://build.opensuse.org/request/show/977080
by user dirkmueller + dimstar_suse
- update to version 2.3.0
- tox: Don't use distutils entrypoint for coverage
- Drop support for Sphinx < 4.x
- Remove six
- Fix exception logging