Run CI also on centos stream 9

[nirs]

Vdsm CI runs only on Centos Stream 8 using python 3.6, so it cannot detect issues with newer packages from Centos Stream 9.

Tasks:

• [ ] Add centos 9 test container
• [ ] Run tests with both centos 8 and 9
• [ ] Update required builds in github configuration

Example workflow running tests on multiple containers:

• https://github.com/oVirt/ovirt-imageio/blob/master/.github/workflows/ci.yml
• https://github.com/oVirt/ovirt-imageio/actions/runs/3154055197