Add prefixes clarification to the doc.

Signed-off-by: Federico Valeri <[email protected]>

documentation/modules/proc-configuring-kafka-bridge-smr-metrics.adoc

@@ -21,8 +21,14 @@ bridge.metrics=strimziMetricsReporter
 +
 Optionally, you can set a comma-separated list of regexes used to filter exposed metrics using the `kafka.prometheus.metrics.reporter.allowlist` property.
 If not set, all available metrics will be exposed.
-+
-You can add any plugin configuration to the Bridge properties file using the `kafka.` prefix.
+
+When needed, it is possible to configure the allowlist per client type.
+For example, set `kafka.admin.prometheus.metrics.reporter.allowlist=` to exclude all admin client metrics.
+
+In case the same property is set with multiple prefixes, the most specific always wins.
+For example, `kafka.producer.prometheus.metrics.reporter.allowlist` wins over `kafka.prometheus.metrics.reporter.allowlist`. 
+
+You can add any plugin configuration to the Bridge properties file using `kafka.`, `kafka.admin`, `kafka.producer`, and `kafka.consumer` prefixes.
 See the https://github.com/strimzi/metrics-reporter[Strimzi Metrics Reporter] documentation for more details.
 
 . Run the Kafka Bridge run script.