fix version in release notes

Author: mgravell

docs/ReleaseNotes.md

@@ -8,6 +8,8 @@ Current package versions:
 
 ## Unreleased
 
+## 2.6.116
+
 - Fix [#2479](https://github.com/StackExchange/StackExchange.Redis/issues/2479): Add `RedisChannel.UseImplicitAutoPattern` (global) and `RedisChannel.IsPattern` ([#2480 by mgravell](https://github.com/StackExchange/StackExchange.Redis/pull/2480))
 - Fix [#2479](https://github.com/StackExchange/StackExchange.Redis/issues/2479): Mark `RedisChannel` conversion operators as obsolete; add `RedisChannel.Literal` and `RedisChannel.Pattern` helpers ([#2481 by mgravell](https://github.com/StackExchange/StackExchange.Redis/pull/2481))
 - Fix [#2449](https://github.com/StackExchange/StackExchange.Redis/issues/2449): Update `Pipelines.Sockets.Unofficial` to `v2.2.8` to support native AOT ([#2456 by eerhardt](https://github.com/StackExchange/StackExchange.Redis/pull/2456))