feat(airflow): Add OPA support to Airflow

[siegfriedweber]

Description

part of stackabletech/airflow-operator#446

Add OPA support to Airflow

Definition of Done Checklist

• Not all of these items are applicable to all PRs, the author should update this template to only leave the boxes in that are relevant
• Please make sure all these things are done and tick the boxes

Tasks

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1. Changes are OpenShift compatible
2. Add an entry to the CHANGELOG.md file
3. Integration tests ran successfully

TIP: Running integration tests with a new product image

The image can be built and uploaded to the kind cluster with the following commands:

bake --product <product> --image-version <stackable-image-version>
kind load docker-image <image-tagged-with-the-major-version> --name=<name-of-your-test-cluster>

See the output of bake to retrieve the image tag for <image-tagged-with-the-major-version>.