Combine set_fact tasks

Where two tasks are being used to set the same fact depending on a when
clause, use a ternary filter to combine them into a single task.

Change-Id: I128781dfad54a9543dac79c2406f1e6808816025

tasks/tempest_resources.yml

@@ -35,17 +35,11 @@
   delay: 15
   when: tempest_service_available_glance | bool
 
-- name: Store tempest image id
-  set_fact:
-    tempest_glance_image_id: "{{ tempest_image_create.id }}"
-  when: tempest_service_available_glance | bool
-
 # This fact is used in tempest.conf.j2; we set an empty string if it doesn't get
 # set above to ensure the template will parse correctly.
-- name: Store empty tempest_glance_image_id fact
+- name: Store tempest image id
   set_fact:
-    tempest_glance_image_id: ''
-  when: not tempest_service_available_glance | bool
+    tempest_glance_image_id: "{{ tempest_service_available_glance | ternary(tempest_image_create.id, '') }}"
 
 - name: Ensure alt tempest image
   os_image:
@@ -60,17 +54,11 @@
   register: tempest_image_alt_create
   when: tempest_service_available_glance | bool
 
-- name: Store alt tempest image id
-  set_fact:
-    tempest_glance_image_alt_id: "{{ tempest_image_alt_create.id }}"
-  when: tempest_service_available_glance | bool
-
 # This fact is used in tempest.conf.j2; we set an empty string if it doesn't get
 # set above to ensure the template will parse correctly.
-- name: Store empty tempest_glance_image_alt_id fact
+- name: Store alt tempest image id
   set_fact:
-    tempest_glance_image_alt_id: ''
-  when: not tempest_service_available_glance | bool
+    tempest_glance_image_alt_id: "{{ tempest_service_available_glance | ternary(tempest_image_alt_create.id, '') }}"
 
 - name: Ensure tempest tenants
   keystone:
@@ -207,17 +195,11 @@
   register: public_network
   when: tempest_service_available_neutron | bool
 
-- name: Store neutron public network id
-  set_fact:
-    tempest_neutron_public_network_id: "{{ public_network.id }}"
-  when: tempest_service_available_neutron | bool
-
 # This fact is used in tempest.conf.j2; we set an empty string if it doesn't get
 # set above to ensure the template will parse correctly.
-- name: Store empty tempest_neutron_public_network_id fact
+- name: Store neutron public network id
   set_fact:
-    tempest_neutron_public_network_id: ''
-  when: not tempest_service_available_neutron | bool
+    tempest_neutron_public_network_id: "{{ tempest_service_available_neutron | ternary(public_network.id, '') }}"
 
 - name: Ensure private subnet exists
   os_subnet: