Implement Unit Testing for DAGs using PyTest

[esloch]

Description:

Currently, there are no unit tests in place to verify the correctness and functionality of the DAGs within the alertflow/dags directory. This issue aims to introduce unit testing using PyTest framework to ensure the reliability and robustness of the DAGs.

The following tasks will be undertaken:

• Test Setup: Create a dedicated test directory structure and configuration files for running PyTest.

• Test Cases: Write comprehensive test cases to cover various scenarios and edge cases for each DAG. Test cases should focus on validating the correctness of task dependencies, parameterization, and expected outcomes.

• Continuous Integration: Integrate the test suite into the project's CI/CD pipeline to automatically run the tests on every code change or scheduled basis.