yamllint: Lint all the YAML files
    
    For now, a list of YAML files' paths is hardcoded (even after
    globbing) into Makefile.am. Moreover, Azure templates are not
    checked at all until Azure triggered.
    
    With this change, the list of YAMLs is populated automatically
    on yamllinting.
    
    Jinja templates are not parseable by a regular yaml module, to
    skip such the YAML_TEMPLATE_FILES is utilized.
    
    Fixes: https://pagure.io/freeipa/issue/8202
    Signed-off-by: Stanislav Levin <slev@altlinux.org>
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>