Add related_bug() to 1629110's test

test_update_attached_volume_with_nonexistent_volume_in_body has been
created for bug 1629110.
So this patch adds related_bug() for knowing related launchpad link
when the test fails on some envs.

Related-Bug: #1629110
Change-Id: I4f11831c03bb19955b90dbb6dbb6a992c9ea41c4
diff --git a/tempest/api/compute/admin/test_volumes_negative.py b/tempest/api/compute/admin/test_volumes_negative.py
index b9dac6f..26b8742 100644
--- a/tempest/api/compute/admin/test_volumes_negative.py
+++ b/tempest/api/compute/admin/test_volumes_negative.py
@@ -49,6 +49,7 @@
                           self.server['id'], nonexistent_volume,
                           volumeId=volume['id'])
 
+    @test.related_bug('1629110', status_code=400)
     @test.idempotent_id('7dcac15a-b107-46d3-a5f6-cb863f4e454a')
     def test_update_attached_volume_with_nonexistent_volume_in_body(self):
         volume = self.create_volume()