Fix broken link in Correlate RUM and Traces for Flutter (#29317)

Docs linked to the Setup page which had no section for Automatic Resource Tracking. Moved to the Advanced Configuration page under "Automatically track resources"

Author: fuzzybinary

content/en/real_user_monitoring/correlate_with_other_telemetry/apm/_index.md

@@ -281,7 +281,7 @@ To start sending just your iOS application's traces to Datadog, see [iOS Trace C
 
 1. Set up [RUM Flutter Monitoring][1].
 
-2. Follow the instructions under [Automatic Resource Tracking][2] to include the Datadog Tracking HTTP Client package and enable HTTP tracking. This includes the following changes to your initialization to add a list of internal, first-party origins called by your Flutter application:
+2. Follow the instructions under [Automatically track resources][2] to include the Datadog Tracking HTTP Client package and enable HTTP tracking. This includes the following changes to your initialization to add a list of internal, first-party origins called by your Flutter application:
     ```dart
     final configuration = DatadogConfiguration(
       // ...
@@ -291,8 +291,7 @@ To start sending just your iOS application's traces to Datadog, see [iOS Trace C
     ```
 
 [1]: /real_user_monitoring/mobile_and_tv_monitoring/flutter/setup/
-[2]: /real_user_monitoring/mobile_and_tv_monitoring/flutter/setup/#automatic-resource-tracking
-
+[2]: /real_user_monitoring/mobile_and_tv_monitoring/flutter/advanced_configuration#automatically-track-resources
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