Update release notes for 2.8.22

Author: NickCraver

docs/ReleaseNotes.md

@@ -7,8 +7,11 @@ Current package versions:
 | [![StackExchange.Redis](https://img.shields.io/nuget/v/StackExchange.Redis.svg)](https://www.nuget.org/packages/StackExchange.Redis/) | [![StackExchange.Redis](https://img.shields.io/nuget/vpre/StackExchange.Redis.svg)](https://www.nuget.org/packages/StackExchange.Redis/) | [![StackExchange.Redis MyGet](https://img.shields.io/myget/stackoverflow/vpre/StackExchange.Redis.svg)](https://www.myget.org/feed/stackoverflow/package/nuget/StackExchange.Redis) |
 
 ## Unreleased
+No pending unreleased changes.
 
-- Update *envoy* command definitions to [allow `UNWATCH`](https://github.com/envoyproxy/envoy/pull/37620) ([#2824 by mgravell](https://github.com/StackExchange/StackExchange.Redis/pull/2824))
+## 2.8.24
+
+- Update Envoy command definitions to [allow `UNWATCH`](https://github.com/envoyproxy/envoy/pull/37620) ([#2824 by mgravell](https://github.com/StackExchange/StackExchange.Redis/pull/2824))
 
 ## 2.8.22