The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

I updated the example which was already there to have some data which look like more "real world" example. I dont know if it's enough? Usually we do not mix up services in our sample dags, that's why I did not include any Xcom example. If you think it is really needed to have an example which uses another service and Xcom to push the results into S3, I'll do that

Usually we do not mix up services in our sample dags

It doesn't have to be. Example dags may serve more than one purpose - in this case my goal was to show that the data is actually metadata but I'm OK with leaving it as is.