test_user_certificate.yml: Use result.failed also for failed_when

For failed_when result.failed should be used to make sure that
the task fails if there was an error.

Fixed also "User test cert members present again" task, it was failing
due to also having first and last parameters with action: member.

tests/user/certificate/test_user_certificate.yml

@@ -32,21 +32,19 @@
       - "{{ lookup('file', 'cert3.b64', rstrip=False) }}"
       action: member
     register: result
-    failed_when: not result.changed
+    failed_when: not result.changed or result.failed
 
   - name: User test cert members present again
     ipauser:
       ipaadmin_password: SomeADMINpassword
       name: test
-      first: test
-      last: test
       certificate:
       - "{{ lookup('file', 'cert1.b64', rstrip=False) }}"
       - "{{ lookup('file', 'cert2.b64', rstrip=False) }}"
       - "{{ lookup('file', 'cert3.b64', rstrip=False) }}"
       action: member
     register: result
-    failed_when: result.changed
+    failed_when: result.changed or result.failed
 
   - name: User test cert members absent
     ipauser:
@@ -59,7 +57,7 @@
       state: absent
       action: member
     register: result
-    failed_when: not result.changed
+    failed_when: not result.changed or result.failed
 
   - name: User test cert members absent again
     ipauser:
@@ -72,7 +70,7 @@
       state: absent
       action: member
     register: result
-    failed_when: result.changed
+    failed_when: result.changed or result.failed
 
   - name: User test absent
     ipauser:
@@ -80,7 +78,7 @@
       name: test
       state: absent
     register: result
-    failed_when: not result.changed
+    failed_when: not result.changed or result.failed
 
   - name: Remove certificate files.
     shell: