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
airflow/providers/google/cloud/operators/bigquery.py
:param delegate_to: The account to impersonate using domain-wide delegation of authority,
        if any. For this to work, the service account making the request must have
        domain-wide delegation enabled.
    :type delegate_to: str
    :param udf_config: The User Defined Function configuration for the query.
        See https://cloud.google.com/bigquery/user-defined-functions for details.
    :type udf_config: list
    :param use_legacy_sql: Whether to use legacy SQL (true) or standard SQL (false).
    :type use_legacy_sql: bool
    :param maximum_billing_tier: Positive integer that serves as a multiplier
        of the basic price.
        Defaults to None, in which case it uses the value set in the project.
    :type maximum_billing_tier: int
    :param maximum_bytes_billed: Limits the bytes billed for this job.
        Queries that will have bytes billed beyond this limit will fail
        (without incurring a charge). If unspecified, this will be
        set to your project default.
    :type maximum_bytes_billed: float
    :param api_resource_configs: a dictionary that contain params
        'configuration' applied for Google BigQuery Jobs API:
        https://cloud.google.com/bigquery/docs/reference/rest/v2/jobs
        for example, {'query': {'useQueryCache': False}}. You could use it
        if you need to provide some params that are not supported by BigQueryOperator
        like args.
    :type api_resource_configs: dict
    :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: Optional[Union[list, tuple, set]]
    :param query_params: a list of dictionary containing query parameter types and
        values, passed to BigQuery. The structure of dictionary should look like