ara: check for return code instead of succeed

In Ansible-2.4, the |succeed behavior changed and always return True
when task uses 'failed_when: false'.
Also uses "type -p" instead of "which" that is used in other roles.

Change-Id: Iddcff07a40dc6c36a1a1c2101a7822697cdbbc34

roles/emit-ara-html/tasks/main.yaml

@@ -12,13 +12,13 @@
     - ara_save_database | bool
 
 - name: Check for ARA install
-  command: which ara
+  command: bash -c "type -p ara"
   ignore_errors: yes
   register: ara_command_type
   when: ara_db_stat.stat.exists
 
 - when:
-    - ara_command_type | succeeded
+    - ara_command_type.rc == 0
     - not ara_command_type | skipped
   block:
     # Always generate (true), never (false) or only on failure ('failure')