Unable to install undercloud due to certmonger issue

Issue

• openstack undercloud install fails with the following errors:

2019-12-13 22:41:17,151 INFO: ESC[1;31mError: /Stage[main]/Tripleo::Profile::Base::Certmonger_user/Tripleo::Certmonger::Haproxy[undercloud-haproxy-public]/Certmonger_certificate[undercloud-haproxy-public-cert]: Could not evaluate: The certificate 'undercloud-haproxy-public-cert' wasn't found in the list.ESC[0m
2019-12-13 22:42:07,372 INFO: ESC[1;31mError: /Stage[main]/Tripleo::Profile::Base::Certmonger_user/Tripleo::Certmonger::Haproxy[undercloud-haproxy-public]/Concat[/etc/pki/tls/certs/undercloud-10.10.10.10.pem]/Concat_file[/etc/pki/tls/certs/undercloud-10.10.10.10.pem]: Failed to generate additional resources using 'eval_generate': undefined method `join' for "/etc/pki/tls/certs/undercloud-front.crt":StringESC[0m