Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1795134
Since we cannot backport this to Fedora 32 due to Python 3.4, I've removed
legacy parts of the spec file:
- %python_provide is not needed on Fedora 33+
- Conflicts with Python 2 versions of python-wheel is not needed after 3 releases
Updated the description to match current upstream one.
Moved the build of the wheel to %install because the new source structure
requires wheel installed in order to use setup.py bdist_wheel.
Reordered the spec a bit.
Also, remove the unused python26 test dependency.
