api-testing.py update

[arthuriansoft]

Describe the bug
The api-test.py file does not work as it tries to call update_credentials() on line 43 which doesn't exist in AquaTempConfigManager.

To Reproduce
Steps to reproduce the behavior:

1. Create venv.
2. Install requirements.
3. Run tests/api-testing.py
4. See error

Expected behavior
Successfully run test.

Screenshots
N/A

Desktop (please complete the following information):
Linux

Smartphone (please complete the following information):
N/A

Additional context
None.