refactor: fix clash with autodiscovery

[JuroOravec]

Fixes https://github.com/EmilStenstrom/django-components/issues/431

This was a lot of trial and error, but it seems that by using importlib.import_module(module_name), we don't have to interact with the sys.modules. Instead, we just pass it a python import like "myapp.components.calendar". And so, there are no conflcts with 3rd party libraries anymore.

I wonder what would be a good way to test this:

• I tried adding a django.py to one of the test_structures (e.g. tests/test_structures/test_structure_1/components/django/django.py), but it didn't get picked up.
• I checked if things worked or not by having a django.py component in the sampleproject (sampleproject/components/django/django.py). That worked, but don't know if we want to use the demo project for testing.
• I was thinking that maybe we could have a full django project for end-to-end tests? But didn't want to tinker with that as part of this issue. Maybe we could add that to the milesone for v1? What do you think @EmilStenstrom?

[EmilStenstrom]

Released as part of 0.66, great work @JuroOravec!