**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/hooks/bigquery.py
self,
        sql: str,
        parameters: Optional[Union[Iterable, Mapping]] = None,
        dialect: Optional[str] = None,
        **kwargs,
    ) -> DataFrame:
        """
        Returns a Pandas DataFrame for the results produced by a BigQuery
        query. The DbApiHook method must be overridden because Pandas
        doesn't support PEP 249 connections, except for SQLite. See:
        https://github.com/pydata/pandas/blob/master/pandas/io/sql.py#L447
        https://github.com/pydata/pandas/issues/6900
        :param sql: The BigQuery SQL to execute.
        :type sql: str
        :param parameters: The parameters to render the SQL query with (not
            used, leave to override superclass method)
        :type parameters: mapping or iterable
        :param dialect: Dialect of BigQuery SQL – legacy SQL or standard SQL
            defaults to use `self.use_legacy_sql` if not specified
        :type dialect: str in {'legacy', 'standard'}
        :param kwargs: (optional) passed into pandas_gbq.read_gbq method