Fix indentation in releasenotes

This commit fixes indentations in releasenotes. Due to the indentations,
the html contents are rendered as block quotes which is awkward.

Change-Id: Ia9f271ead6a6e3fb90afc935771e8da4d8990c3c
diff --git a/releasenotes/notes/tempest-rocky-release-0fc3312053923380.yaml b/releasenotes/notes/tempest-rocky-release-0fc3312053923380.yaml
index e9c77a6..8406be6 100644
--- a/releasenotes/notes/tempest-rocky-release-0fc3312053923380.yaml
+++ b/releasenotes/notes/tempest-rocky-release-0fc3312053923380.yaml
@@ -1,12 +1,12 @@
 ---
-prelude: >
+prelude: |
     This release is to tag the Tempest for OpenStack Rocky release.
     After this release, Tempest will support below OpenStack Releases:
 
-      * Rocky
-      * Queens
-      * Pike
-      * Ocata
+    * Rocky
+    * Queens
+    * Pike
+    * Ocata
 
     Current development of Tempest is for OpenStack Stein development
     cycle. Every Tempest commit is also tested against master during