Update deprecated `commitRecord(org.apache.kafka.connect.source.SourceRecord)` found in CPS source connector

Warning:

```
/java-pubsub-group-kafka-connector/src/main/java/com/google/pubsub/kafka/source/CloudPubSubSourceTask.java:[372,15]
commitRecord(org.apache.kafka.connect.source.SourceRecord) in org.apache.kafka.connect.source.SourceTask has been
deprecated
```

`RecordMetadata` has been [added][1] to the method signature for `commitRecord`:

```java
@Override
@SuppressWarnings("deprecation")
public void commitRecord(SourceRecord record) throws InterruptedException {
block.maybeBlockOn(SOURCE_TASK_COMMIT_RECORD);
super.commitRecord(record);
}

@Override
public void commitRecord(SourceRecord record, RecordMetadata metadata) throws InterruptedException {
block.maybeBlockOn(SOURCE_TASK_COMMIT_RECORD_WITH_METADATA);
super.commitRecord(record, metadata);
}
```

[1]: https://github.com/apache/kafka/blob/3.3/connect/runtime/src/test/java/org/apache/kafka/connect/integration/BlockingConnectorTest.java#L640-L651