### Apache Airflow version

main (development)

### What happened

1. When not providing `project_id` to `BigQueryGetDataOperator` in deferrable mode (`project_id=None`), the query generated by `generate_query` method is bugged, i.e.,: 

````sql
from `None.DATASET.TABLE_ID` limit ...
````

2. `as_dict` param does not work `BigQueryGetDataOperator`.

### What you think should happen instead

1. When `project_id` is `None` - it should be removed from the query along with the trailing dot, i.e.,:

````sql
from `DATASET.TABLE_ID` limit ...
````

2. `as_dict` should be added to the serialization method of `BigQueryGetDataTrigger`.

### How to reproduce

1. Create a DAG file with `BigQueryGetDataOperator` defined as follows:
```python
BigQueryGetDataOperator(
        task_id="bq_get_data_op",
        # project_id="PROJECT_ID",  <-- Not provided
        dataset_id="DATASET",
        table_id="TABLE",
        use_legacy_sql=False,
        deferrable=True
    )
````

2. 1. Create a DAG file with `BigQueryGetDataOperator` defined as follows:
```python
BigQueryGetDataOperator(
        task_id="bq_get_data_op",
        project_id="PROJECT_ID",
        dataset_id="DATASET",
        table_id="TABLE",
        use_legacy_sql=False,
        deferrable=True,
        as_dict=True
    )
````

### Operating System

Debian

### Versions of Apache Airflow Providers

_No response_

### Deployment

Official Apache Airflow Helm Chart

### Deployment details

_No response_

### Anything else

The `generate_query` method is not unit tested (which would have prevented it in the first place) - will be better to add one.

### 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)

"""Will run until the table exists in the Google Big Query."""
        hook = BigQueryAsyncHook(gcp_conn_id=self.gcp_conn_id)
        job_id = None
        while True:
            if job_id is not None:
                status = await hook.get_job_status(job_id=job_id, project_id=self.project_id)
                if status == "success":
                    is_partition = await self._partition_exists(
                        hook=hook, job_id=job_id, project_id=self.project_id
                    )
                    if is_partition:
                        yield TriggerEvent(
                            {
                                "status": "success",
                                "message": f"Partition: {self.partition_id} in table: {self.table_id}",
                            }
                        )
                    job_id = None
                elif status == "error":
                    yield TriggerEvent({"status": "error", "message": status})
                    return
                self.log.info("Sleeping for %s seconds.", self.poll_interval)
                await asyncio.sleep(self.poll_interval)
            else:
                job_id = await hook.create_job_for_partition_get(self.dataset_id, project_id=self.project_id)
                self.log.info("Sleeping for %s seconds.", self.poll_interval)
                await asyncio.sleep(self.poll_interval)
    async def _partition_exists(self, hook: BigQueryAsyncHook, job_id: str | None, project_id: str):