### 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)

error_result=False,
            state="DONE",
            done=lambda: False,
        )
        mock_hook.return_value.get_job.return_value = job
        ti = create_task_instance_of_operator(
            BigQueryInsertJobOperator,
            dag_id="dag_id",
            task_id="insert_query_job",
            configuration=configuration,
            location=TEST_DATASET_LOCATION,
            job_id=job_id,
            project_id=TEST_GCP_PROJECT_ID,
            reattach_states={"PENDING"},
            deferrable=True,
        )
        with pytest.raises(AirflowException) as exc:
            ti.task.execute(MagicMock())
        expected_exception_msg = (
            f"Job with id: {real_job_id} already exists and is in {job.state} state. "
            f"If you want to force rerun it consider setting `force_rerun=True`."
            f"Or, if you want to reattach in this scenario add {job.state} to `reattach_states`"
        )
        assert str(exc.value) == expected_exception_msg
        mock_hook.return_value.get_job.assert_called_once_with(
            location=TEST_DATASET_LOCATION,
            job_id=real_job_id,
            project_id=TEST_GCP_PROJECT_ID,
        )
class TestBigQueryIntervalCheckOperator: