fix link for trace_methods migration (#914)

Author: SylvainJuge

docs/reference/edot-java/migration.md

@@ -110,7 +110,7 @@ For example: `OTEL_RESOURCE_ATTRIBUTES=alice=first,bob=second`. Such labels will
 
 ### `trace_methods`
 
-The Elastic [`trace_methods`] option can be replaced by the [`OTEL_INSTRUMENTATION_METHODS_INCLUDE`](https://opentelemetry.io/docs/zero-code/java/agent/annotations/#creating-spans-around-methods-with-otelinstrumentationmethodsinclude) OpenTelemetry option, however the syntax is different and the ability to use wildcards is more limited.
+The Elastic [`trace_methods`](https://www.elastic.co/docs/reference/apm/agents/java/config-core#config-trace-methods) option can be replaced by the [`OTEL_INSTRUMENTATION_METHODS_INCLUDE`](https://opentelemetry.io/docs/zero-code/java/agent/annotations/#creating-spans-around-methods-with-otelinstrumentationmethodsinclude) OpenTelemetry option, however the syntax is different and the ability to use wildcards is more limited.
 
 ### `capture_jmx_metrics`