add basic fedora support

[Wunderharke]

7330992 fixed the major_version compare and made Fedora deployments to use setup_redhat8.yml. This however broke the script on fedora as there is no EPEL package. This commit adds very basic fedora support by:

1. Separates task into own file (for RedHat OS with major version > 30)
2. removes EPEL task for fedora
3. replaces docker-ce repo details

Not sure whether docker-py is necessary for fedora.

[spantaleev]

I removed some misleading with_items statements and merged this. Thanks! 👍

If you think the playbook works well on Fedora now, we can also update docs/prerequisites.md and mention it.

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Not sure whether docker-py is necessary for fedora.

You can try yum removing it on your system, removing it from roles/matrix-base/tasks/server_base/setup_fedora.yml and re-running the playbook. If nothing breaks, it's likely not necessary (well, or you're not hitting any tasks that require it).

As per the docker_image_module requirements, it seems necessary:

Docker SDK for Python: Please note that the docker-py Python module has been superseded by docker (see here for details). For Python 2.6, docker-py must be used. Otherwise, it is recommended to install the docker Python module. Note that both modules should not be installed at the same time. Also note that when both modules are installed and one of them is uninstalled, the other might no longer function and a reinstall of it is required.

Perhaps using the docker Python module instead of docker-py is better.

I think you may be able to:

• stop installing python3-pip
• stop installing docker-py via pip
• install python3-docker using yum instead

To clean up your installation, you probably need to do pip remove docker-py and dnf remove python3-pip.