backup: Remove default parameter from jinja map (#1839)

The default paramater from the jinja map filter has been added in the
2.11.0 release.
However, the downstream ansible operator is still using ansible 2.9
with jinja 2.10.x so using the default parameter leads to the
following error:

TASK [Dump ingress tls secret names from awx spec and data into file]
********************************
The error was: jinja2.exceptions.FilterArgumentError: Unexpected
keyword argument 'default'
fatal: [localhost]: FAILED! => {
  "msg": "Unexpected failure during module execution.",
  "stdout": ""
}

Rather than using the default parameter with the map filter then add the
selectattr filter to get only the items with tls_secret defined and then
get the tls_secret attribute with the map filter.

This also gets rid of the when statement since we always get an empty
list when no tls_secret are present in ingress_hosts so the loop statement
will be skipped on the empty list.

Finally this changes the default value from the ingress_hosts field because
it's a list rather than a string.

https://jinja.palletsprojects.com/en/latest/templates/#jinja-filters.map

Signed-off-by: Dimitri Savineau <dsavinea@redhat.com>

roles/backup/tasks/secrets.yml

@@ -20,9 +20,7 @@
 
 - name: Dump ingress tls secret names from awx spec and data into file
   include_tasks: dump_ingress_tls_secrets.yml
-  with_items:
-    - "{{ awx_spec.spec['ingress_hosts'] | default('') | map(attribute='tls_secret', default='') | select() | list }}"
-  when: awx_spec.spec['ingress_hosts'] | default('') | map(attribute='tls_secret', default='') | select() | list | length
+  with_items: "{{ awx_spec.spec['ingress_hosts'] | default([]) | selectattr('tls_secret', 'defined') | map(attribute='tls_secret') | list }}"
 
 - name: Dump receptor secret names and data into file
   include_tasks: dump_receptor_secrets.yml