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',
            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=(),
            query_params=None,
            labels=None,
            priority='INTERACTIVE',
            time_partitioning=None,
            api_resource_configs=None,
            cluster_fields=None,
            encryption_configuration=encryption_configuration,
        )
    @mock.patch('airflow.providers.google.cloud.operators.bigquery.BigQueryHook')
    def test_execute_list(self, mock_hook):
        operator = BigQueryExecuteQueryOperator(
            task_id=TASK_ID,
            sql=[
                'Select * from test_table',
                'Select * from other_test_table',
            ],
            destination_dataset_table=None,
            write_disposition='WRITE_EMPTY',
            allow_large_results=False,
            flatten_results=None,