API testing module

By now, many changes are pending to be tested and merged for deployment. Looking back at the testing modules of the API, they have not been updated since March 2022 and the data that was used for testing is also missing. It seems that Wilmer was the only one maintaining it. So, this might be a good opportunity to build a new testing module in pytest (like in autosubmit) that considers all the changes since then.

@mcastril @rahme1 do you think that a new testing module inside the API can help the testing suite to also test the API/workers? Or this is out of the scope?