Ensure utility binaries link to the latest versions

The previous code would not move the openstack cli symlinks from
old venv to new ones at either minor or major release upgrades.

This patch changes the code to use a native ansible module instead
of shell commands. The symlinks are now moved to the current venv
and the tasks are idempotent.

Change-Id: If10f83814d1934b430749a33efdbf20408e2fa3d

playbooks/utility-install.yml

@@ -127,20 +127,23 @@
               - "--constraint {{ utility_upper_constraints_url }}"
             venv_pip_packages: "{{ _openstack_client_list | union(utility_pip_packages) }}"
 
+        - name: Create list of binaries to symlink
+          set_fact:
+             _openstack_client_to_symlink: >-
+              {%- set binary_list = [] %}
+              {%- for l in _openstack_client_list %}
+              {%-   set _ = binary_list.append(l | regex_replace('^(?:python-)?(\w*)(?:client)$', '\\1')) %}
+              {%- endfor %}
+              {{- binary_list }}
+          run_once: true
+
         - name: Create symlinks for openstack clients
-          shell: |
-            {% set _bin_name = item | regex_replace('^(?:python-)?(\w*)(?:client)$', '\\1') %}
-            set -e
-            return_code=0
-            if [[ -e "{{ utility_venv_bin }}/{{ _bin_name }}" && ! -L "/usr/local/bin/{{ _bin_name }}" ]]; then
-              ln -sfn {{ utility_venv_bin }}/{{ _bin_name }} /usr/local/bin/{{ _bin_name }}
-              return_code=2
-            fi
-            exit ${return_code}
-          args:
-            executable: /bin/bash
-          with_items: "{{ _openstack_client_list }}"
-          register: _client_symlink
-          changed_when: _client_symlink.rc == 2
-          failed_when: _client_symlink.rc not in [0,2]
+          file:
+            src: "{{ utility_venv_bin }}/{{ item }}"
+            path: "/usr/local/bin/{{ item }}"
+            state: link
+            force: yes
+            follow: false
+          with_items:
+            - "{{ _openstack_client_to_symlink }}"
           notify: "Create openstack client bash_completion script"