Add schemas 108,130,131 improvements to 2.16.28 release

Change-Id: Id5d49de014ba00ae0d5bf3ea00a2749440f8884a
diff --git a/pages/site/releases/2.16.md b/pages/site/releases/2.16.md
index 4aa7571..bf80c6f 100644
--- a/pages/site/releases/2.16.md
+++ b/pages/site/releases/2.16.md
@@ -726,6 +726,10 @@
   * [Change 302923](https://gerrit-review.googlesource.com/302923):
   Warm PostgreSQL DB before migration.
 
+  * [Change 321635](https://gerrit-review.googlesource.com/c/gerrit/+/321635)
+    [Change 319997](https://gerrit-review.googlesource.com/c/gerrit/+/319997):
+  Parallelize schemas 108,130,131 which perform updates on each repository.
+
   * [Issue 14097](https://gerrit-review.googlesource.com/14097):
   Fix display the GC action on project commands for Gerrit in multi-site configuration.