add change notice

Co-authored-by: Travis Ralston <travpc@gmail.com>

content/client-server-api/modules/account_data.md

@@ -31,6 +31,11 @@ that the server manages. Currently, this only includes
 [`m.fully_read`](#mfully_read) and [`m.push_rules`](#mfully_read).
 This applies to both global and room-specific account data.
 
+{{% boxes/note %}}
+{{% changed-in v="1.10" %}} `m.push_rules` was added to the rejection
+list.
+{{% /boxes/note %}}
+
 Servers must allow clients to read the above event types as normal. Note that
 `m.fully_read` only exists for room-specific account data and `m.push_rules`
 only exists for global account data.