Add tags to allow filter DAGs by tag

Problem to solve

The files-airflow bundle does not automatically add tags while generating the DAGs from meltano schedules.

Further details

It would be nice to have the pipeline details like extractor name, loader name etc. available as airflow DAG tags so that the DAGs search in airflow webserver can be achieved using tags. Additionally it would be nice to present the transform (dbt model) tags into airflow DAGs tags.

Proposal

The extractors and loaders details can easily be extracted from the output of schedule list --format=json and added as tags argument here. Similarity DBT tags can be extracted using dbt ls

What does success look like, and how can we measure that?

Pipeline details and transform (dbt) tags available on meltano UI. image

Regression test

Ensure that DagBag is able to load the meltano DAGs successfully (without an error) from orchestrate/dags/meltano.py file

Links / references

https://airflow.apache.org/docs/apache-airflow/stable/howto/add-dag-tags.html