The tripleo validator CLI has been refactored to be faster (no more Mistral dependence) and new subcommands have been created to be more compliant with all the openstack CLI. This should be backported in stein (this CLI appeared in Stein) to avoid confusion and get a better consistency between Ussuri, Train and Stein.
According to our records, this should be resolved by python-tripleoclient-11.5.3-0.20200114200459.d09212f.el8ost. This build is available now.