Input stream: Debezium messages, with a field with type `bytes`

I need to write it with the JDBC connector to postgres in a `bytea` field.

It crashed in the connector with the following stack.
```
org.apache.kafka.connect.errors.ConnectException: Failed to process a sink record
at io.debezium.connector.jdbc.JdbcChangeEventSink.execute(JdbcChangeEventSink.java:72)
at io.debezium.connector.jdbc.JdbcSinkConnectorTask.put(JdbcSinkConnectorTask.java:93)
at org.apache.kafka.connect.runtime.WorkerSinkTask.deliverMessages(WorkerSinkTask.java:581)
at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:333)
at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:234)
at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:203)
at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:189)
at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:244)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: java.lang.NullPointerException: Cannot invoke "org.hibernate.metamodel.mapping.JdbcMapping.getJdbcValueBinder()" because "jdbcMapping" is null
at org.hibernate.sql.exec.internal.AbstractJdbcParameter.bindParameterValue(AbstractJdbcParameter.java:108)
at org.hibernate.sql.exec.internal.AbstractJdbcParameter.bindParameterValue(AbstractJdbcParameter.java:98)
at org.hibernate.sql.exec.internal.StandardJdbcMutationExecutor.execute(StandardJdbcMutationExecutor.java:74)
at org.hibernate.query.sql.internal.NativeNonSelectQueryPlanImpl.executeUpdate(NativeNonSelectQueryPlanImpl.java:78)
at org.hibernate.query.sql.internal.NativeQueryImpl.doExecuteUpdate(NativeQueryImpl.java:820)
at org.hibernate.query.spi.AbstractQuery.executeUpdate(AbstractQuery.java:643)
at io.debezium.connector.jdbc.JdbcChangeEventSink.writeUpsert(JdbcChangeEventSink.java:258)
at io.debezium.connector.jdbc.JdbcChangeEventSink.write(JdbcChangeEventSink.java:217)
at io.debezium.connector.jdbc.JdbcChangeEventSink.execute(JdbcChangeEventSink.java:69)
... 12 more
```

The issue is the current value has type `java.nio.HeapByteBuffer`, which does not seems to be handled correctly. Seems to work with `byte[]`.

I did a quick patch to solve it (see PR), but I'm not sure this is the good way to handle this.