Record and playback tests with API calls

[vkresch]

DISCLAIMER: Please ignore the yaml files in the cassettes folders for the review. These are vcr generated recordings.

Refactor tests, make them green while enabling record and playback. Do not be discouraged by the line change amount since most of the yaml recordings are being added to the repo.

This PR resolves the issue https://github.com/tezos-reward-distributor-organization/tezos-reward-distributor/issues/547. The following steps were performed:

• Analysis: Avoid to many API calls and long test runs. We want to test the business logic of TRD and not external APIs which we do not maintain.

• Solution: Record api tests with vcr.py

• Implementation: Rough description/explanation of the implementation choices.

• Performed tests: Tests will run in airplane mode thus reducing the test run time locally and on the CI.

• Documentation: IN PROGRESS

• Check list:

• [x] I extended the Github Actions CI test units with the corresponding tests for this new feature (if needed).

• [ ] I extended the Sphinx documentation (if needed).

• [ ] I extended the help section (if needed).

• [ ] I changed the README file (if needed).

• [ ] I created a new issue if there is further work left to be done (if needed).](https://github.com/tezos-reward-distributor-organization/tezos-reward-distributor/issues/547)

Work effort: 20h

[vkresch]

@nicolasochem @jdsika the tests should now run in offline mode. Please test this on your side and let me know if you find an issue. Don't forget to install vcrpy. Thanks!

[nicolasochem]

thank you :+1: