Fix attrs import error on EPEL9
- Resolves: rhbz#2182954
- Enforce tests
Previously failing tests were ignored, which resulted in an EPEL 9 build
being released that was non-functional. This change adds a patch to fix
compatibility with RHEL9's attrs package. It also adds other patches
based on upstream commits to fix some test failures. A handful of tests
had to be skipped for various reasons (see comments) in order to get the
overall suite to run. But now that it runs, we can enforce the tests
and fail the build if something unexpected fails.