Upgrade Kafka client to v2.8.2

It is a non-breaking change, and all clients should
continue to function without any disruptions.

Please review the release notes [1] and upgrade
documentation [2] for more details.

References:
[1] https://archive.apache.org/dist/kafka/2.8.2/RELEASE_NOTES.html
[2] https://kafka.apache.org/28/documentation.html#upgrade

Bug: Issue 323031722
Change-Id: Ica0dc793d7fa0c2d40489b2fd8a5522dc5c2d487

external_plugin_deps.bzl

diff --git a/external_plugin_deps.bzl b/external_plugin_deps.bzl
index 49673fa..0ae5935 100644
--- a/external_plugin_deps.bzl
+++ b/external_plugin_deps.bzl
@@ -3,8 +3,8 @@
 def external_plugin_deps():
     maven_jar(
         name = "kafka-client",
-        artifact = "org.apache.kafka:kafka-clients:2.3.1",
-        sha1 = "21664b0318d201ec412f9b02357b07ba94009c87",
+        artifact = "org.apache.kafka:kafka-clients:2.8.2",
+        sha1 = "b078c76ec2cf00803417c6505ebc8bef1a66d4db",
     )
 
     maven_jar(

src/main/java/com/googlesource/gerrit/plugins/kafka/publish/KafkaRestProducer.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/kafka/publish/KafkaRestProducer.java b/src/main/java/com/googlesource/gerrit/plugins/kafka/publish/KafkaRestProducer.java
index 2f8b51c..f418963 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/kafka/publish/KafkaRestProducer.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/kafka/publish/KafkaRestProducer.java
@@ -30,6 +30,7 @@
 import org.apache.http.client.methods.HttpPost;
 import org.apache.http.entity.ContentType;
 import org.apache.http.entity.StringEntity;
+import org.apache.kafka.clients.consumer.ConsumerGroupMetadata;
 import org.apache.kafka.clients.consumer.OffsetAndMetadata;
 import org.apache.kafka.clients.producer.Callback;
 import org.apache.kafka.clients.producer.Producer;
@@ -71,6 +72,13 @@
   }
 
   @Override
+  public void sendOffsetsToTransaction(
+      Map<TopicPartition, OffsetAndMetadata> map, ConsumerGroupMetadata consumerGroupMetadata)
+      throws ProducerFencedException {
+    unsupported();
+  }
+
+  @Override
   public void commitTransaction() throws ProducerFencedException {
     unsupported();
   }