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
labels=None,
                    priority='INTERACTIVE',
                    time_partitioning=None,
                    api_resource_configs=None,
                    cluster_fields=None,
                    encryption_configuration=None,
                ),
                mock.call(
                    sql='Select * from other_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=None,
                ),
            ]
        )
    @mock.patch('airflow.providers.google.cloud.operators.bigquery.BigQueryHook')
    def test_execute_bad_type(self, mock_hook):