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/always/test_project_structure.py
#
#
import ast
import glob
import itertools
import mmap
import os
import unittest
from typing import List
from parameterized import parameterized
ROOT_FOLDER = os.path.realpath(
    os.path.join(os.path.dirname(os.path.realpath(__file__)), os.pardir, os.pardir)
)
class TestProjectStructure(unittest.TestCase):
    def test_reference_to_providers_from_core(self):
        for filename in glob.glob(f"{ROOT_FOLDER}/example_dags/**/*.py", recursive=True):
            self.assert_file_not_contains(filename, "providers")
    def test_deprecated_packages(self):
        path_pattern = f"{ROOT_FOLDER}/airflow/contrib/**/*.py"
        for filename in glob.glob(path_pattern, recursive=True):
            if filename.endswith("/__init__.py"):
                self.assert_file_contains(filename, "This package is deprecated.")
            else:
                self.assert_file_contains(filename, "This module is deprecated.")
    def assert_file_not_contains(self, filename: str, pattern: str):
        with open(filename, 'rb', 0) as file, mmap.mmap(file.fileno(), 0, access=mmap.ACCESS_READ) as content:
            if content.find(bytes(pattern, 'utf-8')) != -1:
                self.fail(f"File {filename} not contains pattern - {pattern}")
    def assert_file_contains(self, filename: str, pattern: str):