### Apache Airflow version

Other Airflow 2 version (please specify below)

### What happened

When running a DAG that is structured like:
```
@dag{dag_id="my_dag", default_args={"retries":0"}}
def dag():
    op = MyOperator.partial(task_id="my_task", retries=3).expand(...)
```

The following test fails:
```
    def test_retries(self) -> None:
        dag_bag = DagBag(dag_folder=DAG_FOLDER, include_examples=False)
        dag = dag_bag.dags["my_dag"]
        for task in dag.tasks:
            if "my_task" in task.task_id:
                self.assertEqual(3, task.retries) # fails - this is 0
```

When printing out `task.partial_kwargs`, and looking at how the default args and partial args are merged, it seems like the default args are always taking precedence, even though in the `partial` global function, the `retries` do get set later on with the task-level parameter value. This doesn't seem to be respected though.

### What you think should happen instead

_No response_

### How to reproduce

If you run my above unit test for a test DAG, on version 2.4.3, it should show up as a test failure.

### Operating System

OS Ventura

### Versions of Apache Airflow Providers

_No response_

### Deployment

Google Cloud Composer

### Deployment details

_No response_

### Anything else

_No response_

### Are you willing to submit PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

)
    )
    if num_existing_tis:
        
        session.query(TaskInstance).filter(
            TaskInstance.dag_id == mapped.dag_id,
            TaskInstance.task_id == mapped.task_id,
            TaskInstance.run_id == dr.run_id,
        ).delete()
    for index in range(num_existing_tis):
        
        ti = TaskInstance(mapped, run_id=dr.run_id, map_index=index, state=TaskInstanceState.SUCCESS)
        session.add(ti)
    session.flush()
    mapped.expand_mapped_task(dr.run_id, session=session)
    indices = (
        session.query(TaskInstance.map_index, TaskInstance.state)
        .filter_by(task_id=mapped.task_id, dag_id=mapped.dag_id, run_id=dr.run_id)
        .order_by(TaskInstance.map_index)
        .all()
    )
    assert indices == expected
@pytest.mark.parametrize(
    "map_index, expected",
    [
        pytest.param(0, "{{ ds }}", id="0"),
        pytest.param(1, 2, id="1"),
    ],
)
def test_expand_kwargs_render_template_fields_validating_operator(dag_maker, session, map_index, expected):