Apache Airflow version: 1.10.*
BackPort Packages version: 2020.10.29rc1

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/PolideaInternal/airflow/blob/e5307990adb49a5a1c1c88a029940682efee0f9e/airflow/providers/google/cloud/operators/bigquery.py#L2073

However, it would appear that the regex pattern that is attempting to remove the `+` character is not correct as this still remain in `job_id` after `re.sub` is applied.

https://github.com/PolideaInternal/airflow/blob/e5307990adb49a5a1c1c88a029940682efee0f9e/airflow/providers/google/cloud/operators/bigquery.py#L2073

`Invalid job ID "airflow_my_test_dag_v1_test_2020_10_01T00_00_00+00_00_27f69de5cd17a012f3c89d414a70fe64". Job IDs must be alphanumeric (plus underscores and dashes) and must be at most 1024 characters long.
`  

How to reproduce it:

- Create a DAG with the name my-test-dag-v1.
- Run any query against BigQuery using this operator
tests/providers/google/cloud/operators/test_bigquery.py
sql='Select * from test_table',
            dag=self.dag,
            default_args=self.args,
            schema_update_options=None,
        )
        operator.execute(MagicMock())
        mock_hook.return_value.run_query.assert_called_once_with(
            sql='Select * from test_table',
            destination_dataset_table=None,
            write_disposition='WRITE_EMPTY',
            allow_large_results=False,
            flatten_results=None,
            udf_config=None,
            maximum_billing_tier=None,
            maximum_bytes_billed=None,
            create_disposition='CREATE_IF_NEEDED',
            schema_update_options=None,
            query_params=None,
            labels=None,
            priority='INTERACTIVE',
            time_partitioning=None,
            api_resource_configs=None,
            cluster_fields=None,
            encryption_configuration=None,
        )
        self.assertTrue(isinstance(operator.sql, str))
        ti = TaskInstance(task=operator, execution_date=DEFAULT_DATE)
        ti.render_templates()
        self.assertTrue(isinstance(ti.task.sql, str))
    def test_bigquery_operator_extra_serialized_field_when_single_query(self):