firewalld_info: Use module.warn (#715)

* Use module.warn to display warnings instead of module.exit_json

Fixes: #710

Signed-off-by: Abhijeet Kasurde <Akasurde@redhat.com>

tests/integration/targets/firewalld_info/tasks/run_tests_in_started.yml

@@ -20,6 +20,7 @@
 - name: Assert turn active_zones true
   ansible.builtin.assert:
     that:
+      - result.collected_zones == ['public']
 
 - name: Ensure firewalld_zones with zone list
   ansible.posix.firewalld_info:
@@ -31,3 +32,6 @@
 - name: Assert specified zones
   ansible.builtin.assert:
     that:
+      - result.collected_zones == ['public']
+      - result.undefined_zones == ['invalid_zone']
+      - '"invalid_zone" in result.warnings[0]'