Failed to deserialize data for topic [topic] to Avro

Hi,
The plugin, from GitHub's main branch, throws an error when consuming a topic with simple json as well as a topic with avro messages.
I'm using the latest versions of confluentinc Broker, Zookeeper, Connect, and opensearchproject OpenSearch.

I wonder if this is related to the following variable when starting Connect:

` CONNECT_KEY_CONVERTER: io.confluent.connect.avro.AvroConverter`

My config:
```
{
"name": "opensearch-sink",
"config": {
"connector.class": "io.aiven.kafka.connect.opensearch.OpensearchSinkConnector",
"tasks.max": "1",
"topics": "some-existing-topic",
"key.ignore": "true",
"connection.url": "http://opensearch-node1:9200",
"type.name": "kafka-connect"
}
}
```

Connect stack trace
```
[2022-12-09 21:02:36,297] ERROR WorkerSinkTask{id=opensearch-sink-0} Task threw an uncaught and unrecoverable exception. Task is being killed and will not recover until manually restarted (org.apache.kafka.connect.runtime.WorkerTask)
2022-12-09T21:02:36.298045183Z org.apache.kafka.connect.errors.ConnectException: Tolerance exceeded in error handler
2022-12-09T21:02:36.298063297Z at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndHandleError(RetryWithToleranceOperator.java:223)
2022-12-09T21:02:36.298067853Z at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execute(RetryWithToleranceOperator.java:149)
2022-12-09T21:02:36.298071164Z at org.apache.kafka.connect.runtime.WorkerSinkTask.convertAndTransformRecord(WorkerSinkTask.java:513)
2022-12-09T21:02:36.298074122Z at org.apache.kafka.connect.runtime.WorkerSinkTask.convertMessages(WorkerSinkTask.java:493)
2022-12-09T21:02:36.298077269Z at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:332)
2022-12-09T21:02:36.298080134Z at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:234)
2022-12-09T21:02:36.298082970Z at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:203)
2022-12-09T21:02:36.298086088Z at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:188)
2022-12-09T21:02:36.298089054Z at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:243)
2022-12-09T21:02:36.298092333Z at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
2022-12-09T21:02:36.298095317Z at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
2022-12-09T21:02:36.298098179Z at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
2022-12-09T21:02:36.298101007Z at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
2022-12-09T21:02:36.298103968Z at java.base/java.lang.Thread.run(Thread.java:829)
2022-12-09T21:02:36.298107141Z Caused by: org.apache.kafka.connect.errors.DataException: Failed to deserialize data for topic role-received to Avro:
2022-12-09T21:02:36.298110427Z at io.confluent.connect.avro.AvroConverter.toConnectData(AvroConverter.java:124)
2022-12-09T21:02:36.298113334Z at org.apache.kafka.connect.storage.Converter.toConnectData(Converter.java:88)
2022-12-09T21:02:36.298116211Z at org.apache.kafka.connect.runtime.WorkerSinkTask.lambda$convertAndTransformRecord$3(WorkerSinkTask.java:513)
2022-12-09T21:02:36.298122519Z at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndRetry(RetryWithToleranceOperator.java:173)
2022-12-09T21:02:36.298125917Z at org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndHandleError(RetryWithToleranceOperator.java:207)
2022-12-09T21:02:36.298129072Z ... 13 more
2022-12-09T21:02:36.298131874Z Caused by: org.apache.kafka.common.errors.SerializationException: Unknown magic byte!
2022-12-09T21:02:36.298134802Z at io.confluent.kafka.serializers.AbstractKafkaSchemaSerDe.getByteBuffer(AbstractKafkaSchemaSerDe.java:250)
2022-12-09T21:02:36.298174390Z at io.confluent.kafka.serializers.AbstractKafkaAvroDeserializer$DeserializationContext.(AbstractKafkaAvroDeserializer.java:334)
2022-12-09T21:02:36.298181482Z at io.confluent.kafka.serializers.AbstractKafkaAvroDeserializer.deserializeWithSchemaAndVersion(AbstractKafkaAvroDeserializer.java:202)
2022-12-09T21:02:36.298184797Z at io.confluent.connect.avro.AvroConverter$Deserializer.deserialize(AvroConverter.java:172)
2022-12-09T21:02:36.298187722Z at io.confluent.connect.avro.AvroConverter.toConnectData(AvroConverter.java:107)
2022-12-09T21:02:36.298190604Z ... 17 more
```