Update 2.9.1 release notes again

Change-Id: I77bc7b8bde59fac06b5caaa3c9eca5fff9935f78
diff --git a/ReleaseNotes/ReleaseNotes-2.9.1.txt b/ReleaseNotes/ReleaseNotes-2.9.1.txt
index 3e7935f..42422ad 100644
--- a/ReleaseNotes/ReleaseNotes-2.9.1.txt
+++ b/ReleaseNotes/ReleaseNotes-2.9.1.txt
@@ -100,6 +100,6 @@
 
 * Fix handling of permissions for user-specific refs.
 +
-Push permission on refs with username, for example `refs/heads/users/${username}/*`,
-was not honored if this was the only ref on which the user had push
-permission.
+Push permission granted on a ref using the `${username}` placeholder, for
+example `refs/heads/users/${username}/*`, was not honored if this was the
+only ref on which the user had push permission.