Move tests

[ablot]

This PR separates the tests in two.

Everything that already existed and tests individual components of flexiznam is moved to tests/test_conponents, the main folder contains only tests for the main use case. These files should ideally be simple and clear enough to be used as guide for users.

The tests using fake data (empty files with a "good" directory structure and file names) have been deleted to be replaced by test using actual data from the raw_data/demo_project folder. The corresponding yaml are saved in the processed_data/demo_project folder.

Hopefully this should be more helpful and easier to see when we break something.

NB: this PR should not change any file outside of the test folder, except for forgotten cosmetic changes (a r forgotten in attributes in one file)

[ablot]

@znamensk the idea is to keep demo_project in flexilims, the raw data folder and the processed data folder has an actual example instead of a simple pile of garbage (like the current test_project on flexilims). You don't really need to go through all individual changes. If you can just tell me if you are happy to move to mostly local test (impossible to access the data from github) then we can merge.

Once it's done, I would ask everyone that has new data to make a "mouse" in the demo_project raw data folder to have one minimal example of data organisation and always make sure that this is parsed correctly. You can check the folder. The mice have been created but only the 2p physio is populated.

[znamensk]

Yep, happy to keep most tests local.