Bump patch version.

Author: ioquatix

lib/async/version.rb

@@ -4,5 +4,5 @@
 # Copyright, 2017-2024, by Samuel Williams.
 
 module Async
-	VERSION = "2.21.0"
+	VERSION = "2.21.1"
 end

readme.md

@@ -35,6 +35,10 @@ Please see the [project documentation](https://socketry.github.io/async/) for mo
 
 Please see the [project releases](https://socketry.github.io/async/releases/index) for all releases.
 
+### v2.21.1
+
+  - [Worker Pool](https://socketry.github.io/async/releases/index#worker-pool)
+
 ### v2.20.0
 
   - [Traces and Metrics Providers](https://socketry.github.io/async/releases/index#traces-and-metrics-providers)

releases.md

@@ -8,9 +8,7 @@ Ruby 3.4 will feature a new fiber scheduler hook, `blocking_operation_wait` whic
 
 The Async scheduler optionally supports this feature using a worker pool, by using the following environment variable:
 
-```
-ASYNC_SCHEDULER_DEFAULT_WORKER_POOL=true
-```
+    ASYNC_SCHEDULER_DEFAULT_WORKER_POOL=true
 
 This will cause the scheduler to use a worker pool for general blocking operations, rather than blocking the event loop.