PostgreSQL replication stream may fail when refreshing materialized views concurrently [DBZ-6951]

Migrated from [DBZ-6951](https://issues.redhat.com/browse/DBZ-6951)

While materialized views cannot be added to a PostgreSQL publication, there seems to be a corner case where if a materialized view is being refreshed concurrently that the replication connection can end with the following exception:
{noformat}
org.apache.kafka.connect.errors.ConnectException: An exception occurred in the change event producer. This connector will be stopped.
at io.debezium.pipeline.ErrorHandler.setProducerThrowable(ErrorHandler.java:50)
at io.debezium.connector.postgresql.PostgresStreamingChangeEventSource.execute(PostgresStreamingChangeEventSource.java:180)
at io.debezium.connector.postgresql.PostgresStreamingChangeEventSource.execute(PostgresStreamingChangeEventSource.java:41)
at io.debezium.pipeline.ChangeEventSourceCoordinator.streamEvents(ChangeEventSourceCoordinator.java:174)
at io.debezium.pipeline.ChangeEventSourceCoordinator.executeChangeEventSources(ChangeEventSourceCoordinator.java:141)
at io.debezium.pipeline.ChangeEventSourceCoordinator.lambda$start$0(ChangeEventSourceCoordinator.java:109)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: org.postgresql.util.PSQLException: ERROR: unexpected duplicate for tablespace 0, relfilenode 1067889495
at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2675)
at org.postgresql.core.v3.QueryExecutorImpl.processCopyResults(QueryExecutorImpl.java:1263)
at org.postgresql.core.v3.QueryExecutorImpl.readFromCopy(QueryExecutorImpl.java:1163)
at org.postgresql.core.v3.CopyDualImpl.readFromCopy(CopyDualImpl.java:44)
at org.postgresql.core.v3.replication.V3PGReplicationStream.receiveNextData(V3PGReplicationStream.java:160)
at org.postgresql.core.v3.replication.V3PGReplicationStream.readInternal(V3PGReplicationStream.java:125)
at org.postgresql.core.v3.replication.V3PGReplicationStream.readPending(V3PGReplicationStream.java:82)
at io.debezium.connector.postgresql.connection.PostgresReplicationConnection$1.readPending(PostgresReplicationConnection.java:490)
at io.debezium.connector.postgresql.PostgresStreamingChangeEventSource.processMessages(PostgresStreamingChangeEventSource.java:215)
at io.debezium.connector.postgresql.PostgresStreamingChangeEventSource.execute(PostgresStreamingChangeEventSource.java:177)
... 9 more
{noformat}

At the very least, we should document this potential issue in the documentation so that users who may encounter this are aware of why this error occurred and that it's a limitation.

The Zulip chat thread may contain additional details
https://debezium.zulipchat.com/#narrow/stream/348249-community-postgresql/topic/unexpected.20duplicate.20for.20tablespace/near/391702855