Write Tests

Write basic tests that blip works in Django 3 and 4. Also, write tests that will ensure it'll work with `--parallel` flag.

1) Basic Test:
a) Create two folder Django-3 and Django-4 .
b) create a `requirements.txt` and add django 3 and django 4 version and add latest django blip version(I'll add replace to github repo branch, if you can do it than it's good)
b) In those folders create a django project.
c) In `settings.py` add blip as a test runner.
d) create `tests` folder inside these two folder.
Now create two test files `compatibility_test_1.py` and `compatibility_test_2.py`. And add test
```
class CompatibilityTest(TestCase):
def compatibiality_test:
...
```
After this I'll setup the github action.
There will be two steps
Sanity Test Django 3 / 4 (Creates the venv install django 3/4 and blip).

The objective is that simply merging a PR will not break due to syntax error etc.

Feel free to ask if you need some more info.