[Feature] Support specific branch to sync to paimon

### Search before asking

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

### Motivation

In some cases, users may want to sync Fluss's data to a specific branch of Paimon to enable other jobs to write other branches

### Solution

Provides user a configuration to enable the user to specific it...

### Anything else?

_No response_

### Willingness to contribute

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