**Description**

`BigQueryInsertJobOperator` requires the submission of a `configuration` parameter in the form of a dict.  Unfortunately, if this contains a large SQL query - especially one that is formatted with new lines - then this cannot currently be rendered very nicely in the UI.

<img width="1670" alt="Screenshot 2021-07-15 at 15 39 33" src="https://user-images.githubusercontent.com/967119/125806943-839d57a9-d4a0-492d-b130-06432b095239.png">

**Use case / motivation**

The issue with this is that it's impossible to copy and paste the rendered query out of the Airflow UI, into a BigQuery browser and run it without lots of manual edits which is time wasted when troubleshooting problems.

**Are you willing to submit a PR?**

Yes.  My current thought process around this would be to add an optional SQL parameter to the operator which, if provided, would be added into the configuration and could therefore have its own template field and SQL renderer.

e.g.

<img width="1570" alt="Screenshot 2021-07-14 at 14 18 09" src="https://user-images.githubusercontent.com/967119/125808200-5f30b8f4-4def-48a7-8223-82afdc65c973.png">


airflow/providers/google/cloud/operators/bigquery.py
bq_hook = BigQueryHook(
            gcp_conn_id=self.gcp_conn_id,
            delegate_to=self.delegate_to,
            impersonation_chain=self.impersonation_chain,
        )
        return bq_hook.patch_dataset(
            dataset_id=self.dataset_id,
            dataset_resource=self.dataset_resource,
            project_id=self.project_id,
        )
class BigQueryUpdateTableOperator(BaseOperator):
    """
    This operator is used to update table for your Project in BigQuery.
    Use ``fields`` to specify which fields of table to update. If a field
    is listed in ``fields`` and is ``None`` in table, it will be deleted.
    .. seealso::
        For more information on how to use this operator, take a look at the guide:
        :ref:`howto/operator:BigQueryUpdateTableOperator`
    :param dataset_id: The id of dataset. Don't need to provide,
        if datasetId in table_reference.
    :param table_id: The id of table. Don't need to provide,
        if tableId in table_reference.
    :type table_id: str
    :param table_resource: Dataset resource that will be provided with request body.
        https://cloud.google.com/bigquery/docs/reference/rest/v2/tables#resource
    :type table_resource: Dict[str, Any]
    :param fields: The fields of ``table`` to change, spelled as the Table
        properties (e.g. "friendly_name").
    :type fields: List[str]