Typo in Google Cloud Storage sensor: airflow/providers/google/cloud/sensors/gcs/GCSObjectsWithPrefixExistenceSensor

The word _With_ is spelled incorrectly. It should be: GCSObjects**With**PrefixExistenceSensor

**Apache Airflow version**: 2.0.0
**Environment**:
- **Cloud provider or hardware configuration**: Google Cloud
- **OS** (e.g. from /etc/os-release): Mac OS BigSur






tests/deprecated_classes.py
(
        'airflow.providers.microsoft.azure.sensors.wasb.WasbBlobSensor',
        'airflow.contrib.sensors.wasb_sensor.WasbBlobSensor',
    ),
    (
        'airflow.providers.microsoft.azure.sensors.wasb.WasbPrefixSensor',
        'airflow.contrib.sensors.wasb_sensor.WasbPrefixSensor',
    ),
    (
        'airflow.providers.amazon.aws.sensors.glue_catalog_partition.AwsGlueCatalogPartitionSensor',
        'airflow.contrib.sensors.aws_glue_catalog_partition_sensor.AwsGlueCatalogPartitionSensor',
    ),
    (
        'airflow.providers.amazon.aws.sensors.emr_base.EmrBaseSensor',
        'airflow.contrib.sensors.emr_base_sensor.EmrBaseSensor',
    ),
    (
        'airflow.providers.amazon.aws.sensors.emr_job_flow.EmrJobFlowSensor',
        'airflow.contrib.sensors.emr_job_flow_sensor.EmrJobFlowSensor',
    ),
    (
        'airflow.providers.amazon.aws.sensors.emr_step.EmrStepSensor',
        'airflow.contrib.sensors.emr_step_sensor.EmrStepSensor',
    ),
    (
        'airflow.providers.amazon.aws.sensors.sagemaker_base.SageMakerBaseSensor',
        'airflow.contrib.sensors.sagemaker_base_sensor.SageMakerBaseSensor',
    ),
    (
        'airflow.providers.amazon.aws.sensors.sagemaker_endpoint.SageMakerEndpointSensor',