Format multi-line release notes properly

Change-Id: Ia3753f054eb7aee1c9e9a7af77bbefd7693b39f9
diff --git a/releasenotes/notes/add-cascade-parameter-to-volumes-client-ff4f7f12795003a4.yaml b/releasenotes/notes/add-cascade-parameter-to-volumes-client-ff4f7f12795003a4.yaml
index f821a7d..6801858 100644
--- a/releasenotes/notes/add-cascade-parameter-to-volumes-client-ff4f7f12795003a4.yaml
+++ b/releasenotes/notes/add-cascade-parameter-to-volumes-client-ff4f7f12795003a4.yaml
@@ -1,6 +1,7 @@
 ---
 features:
-  - Add cascade parameter to volumes_client.
+  - |
+    Add cascade parameter to volumes_client.
     This option provides the ability to delete a volume and have Cinder
     handle deletion of snapshots associated with that volume by passing
     an additional argument to volume delete, "cascade=True".