Test/label-model

[nifedara]

What does this PR do?

Adds backend test case

• I added a test for Label model creation
• I added Label Factory to factories.py file to isolate its test data
• Contributes to resolving this issue: Implement Backend Test Cases for fAIr hotosm/fAIr#229

Consideration?

• Although some might suggest not testing a model that doesn't have a return statement, I added tests for it as it is nice to have
• I used Black formatter
• I didn't add coverage and factory_boy to the requirement file. So to check coverage and to use factory_boy, you have to install them yourself:
  • pip install coverage and pip install factory_boy

How to test?

• Clone this repo
• Follow the installation guide
• run docker exec -it api bash to run the following commands in the container:
  • coverage run --omit='*/usr/*' manage.py test tests.test_login_model
  • or just coverage run manage.py test tests.test_core_model
  • coverage report (to see a report of the test coverage)