docs: mode NOTE block down below code-example

Author: watson

docs/performance-tuning.asciidoc

@@ -178,8 +178,6 @@ if it is set too low.
 
 An alternative to limiting the maximum number of spans can be to drop spans with a very short duration, as those might not be that relevant.
 
-NOTE: Using a span filter does not reduce the load of recording the spans in your application, but merely filters them out before sending them to the APM Server.
-
 This, however, both reduces the amount of storage needed to store the spans in Elasticsearch, and the bandwidth needed to transport the data to the APM Server from the instrumented application.
 
 This can be implemented by providing a span-filter:
@@ -190,3 +188,5 @@ agent.addSpanFilter(payload => {
   return payload.duration < 10 ? null : payload
 })
 ----
+
+NOTE: Using a span filter does not reduce the load of recording the spans in your application, but merely filters them out before sending them to the APM Server.