[Documentation][Utility] Review docstrings for utility files

A catch-all for the issue to review the remaining python file doctrings not covered by any of the other files under the umbrella issue currently:
- `current_day_conditions.py`
- `e2e_test_results_handler.py`
- `general_constants.py`
- `rufas_time.py`
- `task_manager.py`
- `units.py`
- `user_constants.py`
- `util.py`
- `weather.py`

See umbrella issue for guidelines.