Only invoke the corresponding setUpClass method during it test

feathub_it_test_base.py:

```python
# TODO: only invoke the corresponding base class's setUpClass()
# method to reduce resource consumption.
@classmethod
def invoke_all_base_class_setupclass(cls):
for base_class in cls.__bases__:
if issubclass(base_class, unittest.TestCase):
base_class.setUpClass()
```

Start in feathub_it_test_base.py at invoke_all_base_class_setupclass(), which currently iterates over base classes and calls setUpClass(). Ensure only the corresponding base class's setUpClass() is invoked, with reduced resource consumption as the completion criterion.

Written by the indexing model from the issue text.