Refactor: Convert unittest to pytest in tests/unit_tests/test_helpers.py

[blackboxsw]

This task involves converting the tests within tests/unit_tests/test_cloud.py from unittest.TestCase-based tests to the pytest functional style.

Instructions for Copilot/Assignee:

1. Remove TestCase Inheritance: Convert test classes inheriting from unittest.TestCase into regular Python classes or simply remove the classes and use standalone functions.
2. Convert Assertions: Replace self.assertEqual(...), self.assertTrue(...), etc., with standard assert statements. pytest automatically handles assertion rewriting.
   3.Refactor Setup/Teardown:

• Move setUp() methods to pytest.fixture functions.
• Move tearDown() methods to finalizers in fixtures using yield or addfinalizer.

4. Use mocker instead or mock.patch or mock.call
   5.Handle Exceptions: Replace self.assertRaises(...) with pytest.raises(...) as a context manager.

Acceptance criteria:

• no remaining self.assert*, mock.call or mock.patch uses
• no setUp or teadDown methods
• If common mocks are used for most tests in a class, ensure the test class has a common setup_mocks fixture
• Ensure proper format is applied by running tox -e format
• Run Tests: Ensure all tests with tox -e pytest in the root directory
• Semantic version PATCH value must be incremented in pycloudlib/VERSION
• Ensure all github workflows succeed
• The final squashed changset should be a single git commit which contains the footer 'Fixes GH-<issue_id>'