We were pinning ansible to 2.8 for unittesting but Zuul currently only
supports Ansible 8 and 9. Pin Ansible to 8 in order to better test what
we expect people are using in the wild. This will also enable the
testing of Zuul and Ansible and Zuul Jobs with newer python versions
like 3.12.
In order to run testing with Ansible 8 intsead of 2.8 we drop testing
against python2.7 and python3.8 as neither of them can install an
Ansible version this new.
Change-Id: Icd563def65dcfd40b174218cc4e2b94e0230c374
1f3567396e