Update yamllint config to fix the CI errors
    
    Recently we started seeing CI failing on fi-ansible-lint-diff job, this update
    to yamllint config should fix that. See
    https://ansible.readthedocs.io/projects/lint/rules/yaml/#yamllint-configuration
    for more information about the default yamllint config.
    
    Signed-off-by: Michal Konecny <mkonecny@redhat.com>