Import missing modules when importing all DB models

[potiuk]

Importing all modules did not include importing trigger module, and this caused strange errors when running tests that never imported Trigger separately.

Similaarly Xcom and Variables have not been imported

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[potiuk]

Example errors appearing in xdist tests here:

https://github.com/apache/airflow/actions/runs/12515046642/job/34913595134?pr=44126#step:7:3627

FAILED providers/tests/openlineage/utils/test_utils.py::test_get_user_provided_run_facets_with_multiple_function_definition - sqlalchemy.exc.InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Triggering mapper: 'mapped class AssetModel->asset'. Original exception was: When initializing mapper mapped class AssetModel->asset, expression 'Trigger' failed to locate a name ('Trigger'). If this is a class name, consider adding this relationship() to the <class 'airflow.models.asset.AssetModel'> class after both dependent classes have been defined.
FAILED providers/tests/microsoft/azure/triggers/test_msgraph.py::TestMSGraphTrigger::test_run_when_response_is_bytes - AssertionError: assert equals failed
  'failure'  'success'
FAILED providers/tests/openlineage/utils/test_utils.py::test_get_user_provided_run_facets_with_duplicate_facet_keys - sqlalchemy.exc.InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Triggering mapper: 'mapped class AssetModel->asset'. Original exception was: When initializing mapper mapped class AssetModel->asset, expression 'Trigger' failed to locate a name ('Trigger'). If this is a class name, consider adding this relationship() to the <class 'airflow.models.asset.AssetModel'> class after both dependent classes have been defined.
FAILED providers/tests/openlineage/utils/test_utils.py::test_get_user_provided_run_facets_with_invalid_function_definition - sqlalchemy.exc.InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Triggering mapper: 'mapped class AssetModel->asset'. Original exception was: When initializing mapper mapped class AssetModel->asset, expression 'Trigger' failed to locate a name ('Trigger'). If this is a class name, consider adding this relationship() to the <class 'airflow.models.asset.AssetModel'> class after both dependent classes have been defined.
FAILED providers/tests/openlineage/utils/test_utils.py::test_get_user_provided_run_facets_with_wrong_return_type_function - sqlalchemy.exc.InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Triggering mapper: 'mapped class AssetModel->asset'. Original exception was: When initializing mapper mapped class AssetModel->asset, expression 'Trigger' failed to locate a name ('Trigger'). If this is a class name, consider adding this relationship() to the <class 'airflow.models.asset.AssetModel'> class after both dependent classes have been defined.
FAILED providers/tests/microsoft/azure/triggers/test_msgraph.py::TestMSGraphTrigger::test_serialize - sqlalchemy.exc.InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Triggering mapper: 'mapped class AssetModel->asset'. Original exception was: When initializing mapper mapped class AssetModel->asset, expression 'Trigger' failed to locate a name ('Trigger'). If this is a class name, consider adding this relationship() to the <class 'airflow.models.asset.AssetModel'> class after both dependent classes have been defined.
FAILED providers/tests/microsoft/azure/triggers/test_powerbi.py::TestPowerBITrigger::test_powerbi_trigger_serialization - sqlalchemy.exc.InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Triggering mapper: 'mapped class AssetModel->asset'. Original exception was: When initializing mapper mapped class AssetModel->asset, expression 'Trigger' failed to locate a name ('Trigger'). If this is a class name, consider adding this relationship() to the <class 'airflow.models.asset.AssetModel'> class after both dependent classes have been defined.
FAILED providers/tests/openlineage/utils/test_utils.py::test_get_user_provided_run_facets_with_exception - sqlalchemy.exc.InvalidRequestError: One or more mappers failed to initialize - can't proceed with initialization of other mappers. Triggering mapper: 'mapped class AssetModel->asset'. Original exception was: When initializing mapper mapped class AssetModel->asset, expression 'Trigger' failed to locate a name ('Trigger'). If this is a class name, consider adding this relationship() to the <class 'airflow.models.asset.AssetModel'> class after both dependent classes have been defined.

[potiuk]

lso it is likely that this one was impacting some other ways Airflow DB is initialized: #45236

[potiuk]

I am not sure if we are missing other models here, but generally, depending on what sequence imports happened our DB scripts could "forget" to create certain tables, and our tests were failing with missing associations if referred DB models were not imported in earlier tests.

This is somewhat a weakness of our "imports" doing a lot of work implicitly (and sometimes forgetting to do it).

[potiuk]

Though @uranusjr @ashb -> I am not sure if this is right - I also saw that there are those _getrr calls for all lazy imports, so I am not at all sure if this is the right approach what I am doing - this mechanism of sometimes lazy, sometimes not importing of modules is .... complex ... and I am not sure what the intentions were to have some of the modules lazy and some not... So I am not all sure if what I am doing here is fine.

[potiuk]

Nope. It does not help;