Implement Integration tests for Ingestion DAGs

Create the testing stage in GitLab CI/CD, where the DAGs are tested inside a docker container.

The steps of the task:

• create container with Airflow-server and Flask server mocking external API (Storage and Workflow)

• Trigger the DAGs inside the container with different arguments

• Compare expected and actual results of DAG executions

• Integrate the steps mentioned above into GitLab CI/CD  

• AWS

• Azure

• IBM

• GCP