Module gets imported (hence executed) twice

If a test file contains both an absolute import and a relative import in `parametrize_with_cases`

```python
"""This is module foo.test_bar"""
from foo.bar_data import Var

@parametrize_with_cases("a", cases=".bar_data ")
def test_bar(a):
    pass
```

Then module foo.bar_data is imported twice.
