[BUG] unused submodule imports not removed

[peterchenadded]

Describe the bug

Seems pycln is not able to remove submodule imports that are not used even with the --all flag.

To Reproduce

1. Take this code snippet:

# test_api/a.py
value = 1

# test_api/b.py
value = 2

# test_api/__init__.py

# test.py
import test_api.a
import test_api.b

print(test_api.a.value)

2. Run this Pycln command:

   pycln --all test.py

3. Error traceback or unexpected output (if present):

   No imports are removed

Expected behavior:

1. Description:

Would expect import test_api.b to be removed

3. Expected output (if present):

1 test_api.b should be removed

Environment:

• Python Version: 3.10.6
• Pycln Version: 2.5.0
• OS Type: mac0S m1