Commenting these lines in /etc/hammer/cli_config.yml (as you suggested) causes hammer-cli to work now:
:ssl_client_cert:
:ssl_client_key:
:ssl_with_basic_auth:
Commenting these lines in /etc/hammer/cli_config.yml (as you suggested) causes hammer-cli to work now:
:ssl_client_cert:
:ssl_client_key:
:ssl_with_basic_auth: