Update kafka.asciidoc

The document says the Kafka output works with all Kafka versions in between 0.11 and 2.2.2.
But as per the conversation and confirmation with the developer team in slack thread below it also supports kakfka versions 3.x
https://elastic.slack.com/archives/C0D8SUKB2/p1739435486447789
Hence we need to update our document accordingly.

docs/en/observability/apm/configure/outputs/kafka.asciidoc

@@ -41,7 +41,7 @@ NOTE: Events bigger than <<apm-kafka-max_message_bytes,`max_message_bytes`>> wil
 [[apm-kafka-compatibility]]
 === Compatibility
 
-This output works with all Kafka versions in between 0.11 and 2.2.2. Older versions
+This output works with all Kafka versions in between 0.11 and 3.x Older versions
 might work as well, but are not supported.
 
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