Do not enable epel on EL 10

[spetrosi]

prepare:, how: feature, epel: enabled fails on EL 10. prepare's feature does not provide a way to avoid running on a specific platform. Hence, my prepare passes on all platforms but fails on EL 10 because EL 10 doesn't have epel-release available:

fatal: [[email protected]]: FAILED! => {"changed": false, "failures":
["No package epel-release available."], "msg": "Failed to install some
of the specified packages", "rc": 1, "results": []}

For now, avoid enabling epel on EL 10.

Pull Request Checklist

• [ ] implement the feature
• [ ] write the documentation
• [ ] extend the test coverage
• [ ] update the specification
• [ ] adjust plugin docstring
• [ ] modify the json schema
• [ ] mention the version
• [ ] include a release note