fedora-31 image got broken due to mirrors

[ssbarnea]

Apparently last week the fedora-31 image started to fail in pre phase as it failed to download RPMs from one of fedora mirrors. This clearly counts as zuul infra issue.

repo: downloading from remote: fedora-modular
error: Status code: 403 for http://pubmirror1.math.uh.edu/fedora-buffet/fedora/linux/releases/31/Modular/x86_64/os/repodata/repomd.xml (IP: 129.7.128.189) (http://pubmirror1.math.uh.edu/fedora-buffet/fedora/linux/releases/31/Modular/x86_64/os/repodata/repomd.xml).
error: Status code: 403 for http://pubmirror1.math.uh.edu/fedora-buffet/fedora/linux/releases/31/Modular/x86_64/os/repodata/repomd.xml (IP: 129.7.128.189) (http://pubmirror1.math.uh.edu/fedora-buffet/fedora/linux/releases/31/Modular/x86_64/os/repodata/repomd.xml).
error: Status code: 403 for http://pubmirror1.math.uh.edu/fedora-buffet/fedora/linux/releases/31/Modular/x86_64/os/repodata/repomd.xml (IP: 129.7.128.189) (http://pubmirror1.math.uh.edu/fedora-buffet/fedora/linux/releases/31/Modular/x86_64/os/repodata/repomd.xml).
error: Status code: 403 for http://pubmirror1.math.uh.edu/fedora-buffet/fedora/linux/releases/31/Modular/x86_64/os/repodata/repomd.xml (IP: 129.7.128.189) (http://pubmirror1.math.uh.edu/fedora-buffet/fedora/linux/releases/31/Modular/x86_64/os/repodata/repomd.xml).
Fedora Modular 31 - x86_64                      539  B/s | 199  B     00:00    

https://dashboard.zuul.ansible.com/t/ansible/build/16d1970891534aae8d3969cbf83c15d3

In correlation with unresolved #445 this means that currently we have no way to test py37 and py38 on any zuul node. This is a critical issue as both are current stable versions of python used in production.

Since the last week we where not able to merge anything in molecule* projects.