Polished docs, fixed the build

docs/src/main/asciidoc/spring-cloud-sleuth.adoc

@@ -1207,6 +1207,10 @@ include::../../../../spring-cloud-sleuth-core/src/test/java/org/springframework/
 IMPORTANT: Sleuth does not work with `parallelStream()` out of the box.
 If you want to have the tracing information propagated through the stream, you have to use the approach with `supplyAsync(...)`, as shown earlier.
 
+If there are beans that implement the `Executor` interface that you would like
+to exclude from span creation, you can use the `spring.sleuth.async.ignored-beans`
+property where you can provide a list of bean names.
+
 ===== Customization of Executors
 
 Sometimes, you need to set up a custom instance of the `AsyncExecutor`.