Remove some of the outdated content from upstream.yaml
Remove some of the outdated content from upstream.yaml

A Bugzilla should be filed when upstream supports Python3, instead of
recording that fact here.
The URL field in the RPM is a better place to track where upstream is.
Packages that are py3-compatible do not need to be tracked here
any more.

fedora-python/portingdb,fedora-python/portingdb,fedora-python/portingdb