[datadog_downtime] - added 'type' to recurrence object when rrule param is present (#6811)

* added 'type' to recurrence object when rrule param is present

* formatting cleanup

changelogs/fragments/6811-datadog-downtime-rrule-type.yaml

@@ -0,0 +1,2 @@
+bugfixes:
+  - datadog_downtime - presence of ``rrule`` param lead to the Datadog API returning Bad Request due to a missing recurrence type (https://github.com/ansible-collections/community.general/pull/6811).

plugins/modules/datadog_downtime.py

@@ -248,7 +248,8 @@ def build_downtime(module):
         downtime.timezone = module.params["timezone"]
     if module.params["rrule"]:
         downtime.recurrence = DowntimeRecurrence(
-            rrule=module.params["rrule"]
+            rrule=module.params["rrule"],
+            type="rrule",
         )
     return downtime