**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
:param allow_jagged_rows: Accept rows that are missing trailing optional columns.
            The missing values are treated as nulls. If false, records with missing
            trailing columns are treated as bad records, and if there are too many bad
            records, an invalid error is returned in the job result. Only applicable when
            source_format is CSV.
        :type allow_jagged_rows: bool
        :param encoding: The character encoding of the data.
            .. seealso::
                https://cloud.google.com/bigquery/docs/reference/rest/v2/tables#externalDataConfiguration.csvOptions.encoding
        :type encoding: str
        :param schema_update_options: Allows the schema of the destination
            table to be updated as a side effect of the load job.
        :type schema_update_options: Union[list, tuple, set]
        :param src_fmt_configs: configure optional fields specific to the source format
        :type src_fmt_configs: dict
        :param time_partitioning: configure optional time partitioning fields i.e.
            partition by field, type and  expiration as per API specifications.
        :type time_partitioning: dict
        :param cluster_fields: Request that the result of this load be stored sorted
            by one or more columns. This is only available in combination with
            time_partitioning. The order of columns given determines the sort order.
        :type cluster_fields: list[str]
        :param encryption_configuration: [Optional] Custom encryption configuration (e.g., Cloud KMS keys).
            **Example**: ::
                encryption_configuration = {
                    "kmsKeyName": "projects/testp/locations/us/keyRings/test-kr/cryptoKeys/test-key"
                }
        :type encryption_configuration: dict
        """
        warnings.warn(