[Bug]flink sink .finishConnect(..) failed: Connection refused: /127.0.0.1:6650

### Search before asking

- [X] I searched in the [issues](https://github.com/apache/pulsar/issues) and found nothing similar.

### Version

pulsar and flink run in docker

pulsar version: image: apachepulsar/pulsar:latest
flink version: 1.17.1

flink program dependency:

org.apache.flink
flink-connector-pulsar
4.0.0-1.17

### Minimal reproduce step

PulsarSinkBuilder buider = PulsarSink.builder()
//http://192.168.1.78:8080
.setAdminUrl(conf.getSinkAdminUrl())
//pulsar://192.168.1.78:6650
.setServiceUrl(conf.getSinkServiceUrl())
.setSerializationSchema(new SimpleStringSchema())
.setDeliveryGuarantee(DeliveryGuarantee.AT_LEAST_ONCE);

buider.setTopicRouter(new CustomTopicRouter(topics));
PulsarSink pulsarSink = buider.build();

### What did you expect to see?

no error

### What did you see instead?

finishConnect(..) failed: Connection refused: /127.0.0.1:6650
But i set service url: pulsar://192.168.1.78:6650

org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.ExecutionException: org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650{"previous":[{"attempt":0,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":1,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":2,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":3,"error":"org.apache.pulsar.client.api.PulsarClientException:
java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":4,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":5,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":6,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":7,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":8,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.AbstractChannel$AnnotatedConnectException: finishConnect(..) failed: Connection refused: /127.0.0.1:6650"},{"attempt":9,"error":"org.apache.pulsar.client.api.PulsarClientException: java.util.concurrent.CompletionException: org.apache.pulsar.shade.io.netty.channel.

### Anything else?

_No response_

### Are you willing to submit a PR?

- [ ] I'm willing to submit a PR!

No repository file or test is identified. Start by reproducing the supplied Flink 1.17.1 and Pulsar Docker setup with the PulsarSinkBuilder URLs, then inspect the connector and container networking configuration to determine why the client connects to 127.0.0.1:6650. Done means identifying a reproducible product issue or a clearly documented configuration cause.

Written by the indexing model from the issue text.