**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/operators/bigquery.py
google_cloud_storage_conn_id='airflow-conn-id'
            )
    :type labels: dict
    :param view: [Optional] A dictionary containing definition for the view.
        If set, it will create a view instead of a table:
        .. seealso::
            https://cloud.google.com/bigquery/docs/reference/rest/v2/tables#ViewDefinition
    :type view: dict
    :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
    :param location: The location used for the operation.
    :type location: str
    :param cluster_fields: [Optional] The fields used for clustering.
            Must be specified with time_partitioning, data in the table will be first
            partitioned and subsequently clustered.
            .. seealso::
                https://cloud.google.com/bigquery/docs/reference/rest/v2/tables#clustering.fields
    :type cluster_fields: list
    :param impersonation_chain: Optional service account to impersonate using short-term
        credentials, or chained list of accounts required to get the access_token
        of the last account in the list, which will be impersonated in the request.
        If set as a string, the account must grant the originating account
        the Service Account Token Creator IAM role.
        If set as a sequence, the identities from the list must grant
        Service Account Token Creator IAM role to the directly preceding identity, with first
        account from the list granting this role to the originating account (templated).