class RuboCop::Cop::Chef::Correctness::DnfPackageAllowDowngrades

The ‘dnf_package` resource does not support the `allow_downgrades` property.

@example

### incorrect
dnf_package 'nginx' do
  version '1.2.3'
  allow_downgrades true
end

### correct
dnf_package 'nginx' do
  version '1.2.3'
end