3.0.0: Mention support for signed push with GPG subkeys

Change-Id: I8445d3bd27a8b26056065b9751b94cf29b58a8a7
diff --git a/pages/site/releases/3.0.md b/pages/site/releases/3.0.md
index 5ee9024..ce75bc1 100644
--- a/pages/site/releases/3.0.md
+++ b/pages/site/releases/3.0.md
@@ -22,6 +22,9 @@
   PostgreSQL and MariaDb are also supported. It is also possible for plugins to
   provide another backend by implementing the `AccountPatchReviewStore` interface.
 
+* [Issue 4040](https://bugs.chromium.org/p/gerrit/issues/detail?id=4040):
+Support for signed push with GPG subkeys.
+
 ## Important Notes
 
 ### Schema Changes
diff --git a/pages/site/releases/README.md b/pages/site/releases/README.md
index ac25f4e..efae3f4 100644
--- a/pages/site/releases/README.md
+++ b/pages/site/releases/README.md
@@ -25,6 +25,8 @@
 * The database backend for changes, accounts, groups and projects ("ReviewDb") is
 removed and all metadata is now stored in git ("NoteDb").
 
+* Support for signed push with GPG subkeys.
+
 [Release notes for Gerrit 3.0](/3.0.md)
 
 ## 2.16