GH-3396: Add Docs for Micrometer MeterFilters

Resolves https://github.com/spring-projects/spring-integration/issues/3396

* Add an example.

src/reference/asciidoc/metrics.adoc

@@ -4,7 +4,7 @@
 This section describes how to capture metrics for Spring Integration.
 In recent versions, we have relied more on Micrometer (see https://micrometer.io), and we plan to use Micrometer even more in future releases.
 
-[[configuring-metrics-capture]]
+[[legacy-metrics]]
 ==== Legacy Metrics
 
 Legacy metrics were removed in Version 5.4; see Micrometer Integration below.
@@ -48,6 +48,8 @@ IMPORTANT: `defaultLoggingEnabled` is applied only if you have not explicitly co
 [[micrometer-integration]]
 ==== Micrometer Integration
 
+===== Overview
+
 Starting with version 5.0.3, the presence of a https://micrometer.io/[Micrometer] `MeterRegistry` in the application context triggers support for Micrometer metrics.
 
 To use Micrometer, add one of the `MeterRegistry` beans to the application context.
@@ -118,3 +120,34 @@ and
 * `tag`: `type:channel`
 * `tag`: `name:<componentName>`
 * `description`: `The remaining capacity of the queue channel`
+
+===== Disabling Meters
+
+With the <<legacy-metrics>> (which have now been removed), you could specify which integration components would collect metrics.
+By default, all meters are registered when first used.
+Now, with Micrometer, you can add `MeterFilter` s to the `MeterRegistry` to prevent some or all from being registered.
+You can filter out (deny) meters by any of the properties provided, `name`, `tag`, etc.
+See https://micrometer.io/docs/concepts#_meter_filters[Meter Filters] in the Micrometer documentation for more information.
+
+For example, given:
+
+====
+[source, java]
+----
+@Bean
+public QueueChannel noMeters() {
+    return new QueueChannel(10);
+}
+----
+====
+
+You can suppress registration of meters for just this channel with:
+
+====
+[source, java]
+----
+registry.config().meterFilter(MeterFilter.deny(id ->
+        "channel".equals(id.getTag("type")) &&
+        "noMeters".equals(id.getTag("name"))));
+----
+====