Update APM configuration example in Kubernetes doc (#33425)

* Update APM configuration example in Kubernetes doc

Clarify the usage of 'enabledNamespaces' for disabling APM due to tab separating Agent versions.

* Apply suggestion "Note" and wording on exception

Co-authored-by: Brett Blue <[email protected]>

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Co-authored-by: Brett Blue <[email protected]>

Author: guimspace

content/en/tracing/trace_collection/automatic_instrumentation/single-step-apm/kubernetes.md

@@ -180,6 +180,7 @@ Review the following examples demonstrating how to select specific services:
 
 This configuration:
 - enables APM for all namespaces except the `jenkins` namespace.
+  - **Note**: use `enabledNamespaces` to disable for all namespaces except those listed.
 - instructs Datadog to instrument the Java applications with the default Java APM SDK and Python applications with `v.3.1.0` of the Python APM SDK.
 
 {{< highlight yaml "hl_lines=4-10" >}}