tasks: galera_client_install_zypper: Drop zypper workaround for Ansible < 2.2

openstack-ansible is using Ansible >= 2.3 so we can safely drop the <2.2
workaround for zypper and import the repository keys directly using the
auto_import_keys option.

Change-Id: Ic839829df9f96b3145f8a5d7c77f0f7b04fba12e

tasks/galera_client_install_zypper.yml

@@ -13,25 +13,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# NOTE(hwoarang): zypper_repository/auto_import_keys added in 2.2
-# so we need to manually refresh the repository and import the keys
-# in order to work with older ansible versions.
 - name: Add galera client zypper repository
   zypper_repository:
       refresh: yes
       name: "{{ item.name }}"
       repo: "{{ item.uri }}"
+      auto_import_keys: yes
   register: zypper_repository_added
   with_items: "{{ galera_client_zypper_repo }}"
   tags:
     - galera-repos
-
-# NOTE(hwoarang): We need to run this right after we add the repos and
-# before we install any packages so it can't be a handler unless we
-# move everything to pre_tasks
-- name: Refresh galera client zypper repository
-  command: zypper --gpg-auto-import-keys ref
-  when: zypper_repository_added.changed
-  tags:
-    - skip_ansible_lint
-    - galera-repos