Remove legacy repo format from examples/tests, replace the default with the new standard format except when specifically testing legacy stuff
A whole bunch of our tests are using a format that goes through a deprecated loading process that's different than what we expect our users to use. This caused an issue in prod yesterday where dagster_docker_celery and certain dagster_airflow just stopped working.
This diff replaces all the test yamls that were using it (other than ones specifically designed to test the legacy path),
Test Plan: BK+Azure
Reviewers: alangenfeld, schrockn
Reviewed By: alangenfeld
Differential Revision: https://dagster.phacility.com/D4742