**Apache Airflow version**: 1.10.*
**BackPort Packages version**: 2020.10.5rc1

**What happened**:

`BigQueryInsertJobOperator` tries to start a BigQuery job by specifying a job_id which is a combination of `dag_id`, `task_id`, `execution_date` and an additional `uniqueness_suffix`.

https://github.com/apache/airflow/blob/master/airflow/providers/google/cloud/operators/bigquery.py#L2072

However, because BigQuery only accepts alphanumeric (in additon to dashes and underscore) characters then, if a DagID contains a version number whcih includes a `.` character then this will cause the task to fail.

https://cloud.google.com/bigquery/docs/running-jobs#generate-jobid

**How to reproduce it**:
Create a DAG with the name `my-dag-v1.0`.
airflow/providers/google/cloud/operators/bigquery.py
template_fields = (
        'dataset_id',
        'table_id',
        'max_results',
        'selected_fields',
        'impersonation_chain',
    )
    ui_color = BigQueryUIColors.QUERY.value
    @apply_defaults
    def __init__(
        self,
        *,
        dataset_id: str,
        table_id: str,
        max_results: int = 100,
        selected_fields: Optional[str] = None,
        gcp_conn_id: str = 'google_cloud_default',
        bigquery_conn_id: Optional[str] = None,
        delegate_to: Optional[str] = None,
        location: Optional[str] = None,
        impersonation_chain: Optional[Union[str, Sequence[str]]] = None,
        **kwargs,
    ) -> None:
        super().__init__(**kwargs)
        if bigquery_conn_id:
            warnings.warn(
                "The bigquery_conn_id parameter has been deprecated. You should pass "
                "the gcp_conn_id parameter.",
                DeprecationWarning,
                stacklevel=3,