Add delete_after to swift upload role

The module used by the swift upload supports setting the
x-delete-after header. However this is not plumbed through the role so
do that.

Change-Id: I9404a1c00062e4bb60d00a25b29897d4606df737

roles/wip-upload-logs-swift/README.rst

@@ -47,6 +47,12 @@ This uploads logs to an OpenStack Object Store (Swift) container.
    If the container is created, should it be created with global read
    ACLs.  If the container already exists, it will not be modified.
 
+.. zuul:rolevar:: zuul_log_delete_after
+   :default: 15552000
+
+   Number of seconds to delete objects after upload. Default is 6 months
+   (15552000 seconds) and if set to 0 X-Delete-After will not be set.
+
 .. zuul:rolevar:: zuul_log_path
    :default: Generated by the role `set-zuul-log-path-fact`
 

roles/wip-upload-logs-swift/tasks/main.yaml

@@ -26,6 +26,7 @@
         prefix: "{{ zuul_log_path }}"
         files:
           - "{{ zuul.executor.log_root }}/"
+        delete_after: "{{zuul_log_delete_after | default(omit) }}"
       register: upload_results
 
 - name: Return log URL to Zuul