### Apache Airflow Provider(s)

databricks

### Versions of Apache Airflow Providers

apache-airflow-providers-databricks==1!2.0.2


### Apache Airflow version

2.1.4 (latest released)

### Operating System

Debian GNU/Linux 11 (bullseye)

### Deployment

Docker-Compose

### Deployment details

Running local deployment using Astronomer CLI

### What happened

When calling the `get_run_state` method from the `DatabricksHook`, I get the following error:

`TypeError: Object of type RunState is not JSON serializable`

I think this is due to [the method returning a RunState custom class](https://github.com/apache/airflow/blob/main/airflow/providers/databricks/hooks/databricks.py#L275) as opposed to a `str` like the rest of the methods in the databricks hook (i.e. `get_job_id`, `get_run_page_url`, etc.)

### What you expected to happen

When calling the `get_run_state` method, simply return the `result_state` or `state_message` [variables](https://github.com/apache/airflow/blob/main/airflow/providers/databricks/hooks/databricks.py#L287-L288) instead of the `RunState` class.

### How to reproduce

Create a dag that references a databricks deployment and use this task to see the error:

```
    from airflow.providers.databricks.hooks.databricks import DatabricksHook
    run_id = <insert run id from databricks ui here>

    def get_run_state(self, run_id: str):
           return self.hook.get_run_state(run_id=run_id)

    python_get_run_state = PythonOperator(
        task_id="python_get_run_state",
        python_callable=get_run_state,
        op_kwargs={
            "run_id": str(run_id)
        }
    )
```

### Anything else

_No response_

### Are you willing to submit PR?

- [X] 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)

airflow/providers/databricks/hooks/databricks.py
if not isinstance(other, RunState):
            return NotImplemented
        return (
            self.life_cycle_state == other.life_cycle_state
            and self.result_state == other.result_state
            and self.state_message == other.state_message
        )
    def __repr__(self) -> str:
        return str(self.__dict__)
class DatabricksHook(BaseHook):
    """
    Interact with Databricks.
    :param databricks_conn_id: Reference to the :ref:`Databricks connection <howto/connection:databricks>`.
    :type databricks_conn_id: str
    :param timeout_seconds: The amount of time in seconds the requests library
        will wait before timing-out.
    :type timeout_seconds: int
    :param retry_limit: The number of times to retry the connection in case of
        service outages.
    :type retry_limit: int
    :param retry_delay: The number of seconds to wait between retries (it
        might be a floating point number).
    :type retry_delay: float
    """
    conn_name_attr = 'databricks_conn_id'
    default_conn_name = 'databricks_default'
    conn_type = 'databricks'
    hook_name = 'Databricks'
    def __init__(