Add dag processor deployment

[santosr2]

Note

This issue is imported from the original repository: airflow-helm#577

Checks

• I have checked for existing issues.
• This report is about the User-Community Airflow Helm Chart.

Motivation

As of version 2.3.0, Airflow allows running DagProcessorManager as a standalone process. This PR adds the ability to run a separate deployment for the dag processor component to separate it from the scheduler.

Implementation

Enable it as optional for Airflow 2.X and mandatory in Airflow 3.X

Are you willing & able to help?

• I am able to submit a PR!
• I can help test the feature!

[santosr2]

Including it together with the airflow v3 support, since Dag Processor is mandatory on that version