Description of problem:
openshift-ansible 3.8 playbooks,default value for openshift_metrics_image_version is v3.7, and default value for all logging components are v3.7, these default values should be v3.8

see the values in 3.8 playbooks now:
# grep -r "openshift_metrics_image_version"
roles/openshift_metrics/tasks/main.yaml:    openshift_metrics_image_version: "{{ openshift_metrics_image_version | default(__openshift_metrics_image_version) }}"
roles/openshift_metrics/vars/openshift-enterprise.yml:__openshift_metrics_image_version: "v3.7"


# grep -r "openshift_logging_image_version"
roles/openshift_logging_curator/vars/openshift-enterprise.yml:__openshift_logging_curator_image_version: "{{ openshift_logging_image_version | default ('v3.7') }}"
roles/openshift_logging_elasticsearch/vars/openshift-enterprise.yml:__openshift_logging_elasticsearch_image_version: "{{ openshift_logging_image_version | default ('v3.7') }}"
roles/openshift_logging_elasticsearch/vars/openshift-enterprise.yml:__openshift_logging_elasticsearch_proxy_image_version: "{{ openshift_logging_image_version | default ('v3.7') }}"
roles/openshift_logging_eventrouter/vars/openshift-enterprise.yml:__openshift_logging_eventrouter_image_version: "{{ openshift_logging_image_version | default ('v3.7') }}"
roles/openshift_logging_fluentd/vars/openshift-enterprise.yml:__openshift_logging_fluentd_image_version: "{{ openshift_logging_image_version | default ('v3.7') }}"
roles/openshift_logging_kibana/vars/openshift-enterprise.yml:__openshift_logging_kibana_image_version: "{{ openshift_logging_image_version | default ('v3.7') }}"
roles/openshift_logging_kibana/vars/openshift-enterprise.yml:__openshift_logging_kibana_proxy_image_version: "{{ openshift_logging_image_version | default ('v3.7') }}"
roles/openshift_logging_mux/vars/openshift-enterprise.yml:__openshift_logging_mux_image_version: "{{ openshift_logging_image_version | default ('v3.7') }}"



Version-Release number of the following components:
# rpm -qa | grep openshift-ansible
openshift-ansible-lookup-plugins-3.8.1-1.git.0.0965aca.el7.noarch
openshift-ansible-3.8.1-1.git.0.0965aca.el7.noarch
openshift-ansible-docs-3.8.1-1.git.0.0965aca.el7.noarch
openshift-ansible-callback-plugins-3.8.1-1.git.0.0965aca.el7.noarch
openshift-ansible-roles-3.8.1-1.git.0.0965aca.el7.noarch
openshift-ansible-playbooks-3.8.1-1.git.0.0965aca.el7.noarch
openshift-ansible-filter-plugins-3.8.1-1.git.0.0965aca.el7.noarch



How reproducible:
Always

Steps to Reproduce:
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Actual results:

Expected results:

Additional info: