AutoMLForecastingTrainingJob fails with error 404 Model does not exist

#### Environment details

- OS type and version: Doesn't matter, initially catch in Cloud Composer.
- Python version: 3.11.8
- pip version: 23.2.1
- `google-cloud-aiplatform` version: 1.142.0

#### Steps to reproduce

1. Run AutoMLForecastingTrainingJob.run several times, not simultaneously to not exceed quota.
2. Some runs will fail with error: google.api_core.exceptions.NotFound: 404 The Model does not exist. For me 1-2 of the jobs from 10 failed with this error.

#### Code example

System test from here : https://github.com/apache/airflow/blob/main/providers/google/tests/system/google/cloud/vertex_ai/example_vertex_ai_batch_prediction_job.py

#### Stack trace
```
File "/opt/python3.11/lib/python3.11/site-packages/airflow/providers/google/cloud/hooks/vertex_ai/auto_ml.py", line 706, in create_auto_ml_forecasting_training_job
model = self._job.run(
^^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/cloud/aiplatform/training_jobs.py", line 2212, in run
return self._run(
^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/cloud/aiplatform/base.py", line 862, in wrapper
return method(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/cloud/aiplatform/training_jobs.py", line 2666, in _run
new_model = self._run_job(
^^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/cloud/aiplatform/training_jobs.py", line 855, in _run_job
model = self._get_model(block=block)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/cloud/aiplatform/training_jobs.py", line 953, in _get_model
return models.Model(
^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/cloud/aiplatform/models.py", line 5238, in __init__
self._gca_resource = self._get_gca_resource(resource_name=versioned_model_name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/cloud/aiplatform/base.py", line 691, in _get_gca_resource
return getattr(self.api_client, self._getter_method)(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/cloud/aiplatform_v1/services/model_service/client.py", line 1145, in get_model
response = rpc(
^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/api_core/gapic_v1/method.py", line 131, in __call__
return wrapped_func(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/api_core/retry/retry_unary.py", line 294, in retry_wrapped_func
return retry_target(
^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/api_core/retry/retry_unary.py", line 156, in retry_target
next_sleep = _retry_error_helper(
^^^^^^^^^^^^^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/api_core/retry/retry_base.py", line 214, in _retry_error_helper
raise final_exc from source_exc
File "/opt/python3.11/lib/python3.11/site-packages/google/api_core/retry/retry_unary.py", line 147, in retry_target
result = target()
^^^^^^^^
File "/opt/python3.11/lib/python3.11/site-packages/google/api_core/grpc_helpers.py", line 77, in error_remapped_callable
raise exceptions.from_grpc_error(exc) from exc
google.api_core.exceptions.NotFound: 404 The Model does not exist.
```

I checked model in Google Cloud and model exists, no error or failed status. Maybe Model registry needs more time to deploy the model.

Start at the create_auto_ml_forecasting_training_job entry point shown in the stack trace and inspect the linked Vertex AI system test, example_vertex_ai_batch_prediction_job.py. Reproduce repeated, non-concurrent AutoMLForecastingTrainingJob.run calls and trace when the model lookup occurs. Done means the reported intermittent 404 is addressed and the repeated-run scenario has regression coverage.

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