Fix an issue where the _thirdparty package is not distributed correctly

[Hazhzeng]

Description

This is the root cause of the library where the azure.functions._thirdparty sub-folder failed to reload properly.
The dangling _thirdparty folder is not being treated as a proper Python module.
Thus, when poping out from sys.modules, it is not being recognized as a part of azure.functions. Thus, the topology graph is not built out correctly when removing caches from sys.modules.

Related PR

Azure/azure-functions-python-worker#854

See how azure_functions_worker distribute the _thirdparty package properly

It has __init__.py file defined in it: https://github.com/Azure/azure-functions-python-worker/tree/dev/azure_functions_worker/_thirdparty
It is being included in setup.py: https://github.com/Azure/azure-functions-python-worker/blob/dev/setup.py#L389

How this is found

Using this following code for reloading module.

try:
    module_paths = set(getattr(module, '__path__', None) or [])
    if hasattr(module, '__file__') and module.__file__:
        module_paths.add(module.__file__)

    if any([p for p in module_paths if p.startswith(path)]):
        sys.modules.pop(module_name)
except Exception as e:
    logger.warning(
        f'Attempt to remove module cache for {module_name} but'
        f' failed with {e}. Using the original module cache.'
    )

Failed with
Attempt to remove module cache for azure.functions._thirdparty but failed with 'azure.functions'. Using the original module cache.

More to investigate

I'm not quite sure why this is triggered when the module is hot-reloaded (a.k.a. Linux Consumption). This should also fail in D

[github-actions]

✅ Result of Pytest Coverage

[vrdmr]

LGTM