Try and reduce flakiness of number of test call asserts

[amoghrajesh]

Saw such failures in CI:

TestDbtCloudRunJobOperator.test_execute_wait_for_termination[default_account-2-timeout] _
providers/tests/dbt/cloud/operators/test_dbt.py:290: in test_execute_wait_for_termination
    assert mock_get_job_run.call_count == 4
E   AssertionError: assert 2 == 4
E    +  where 2 = <MagicMock name='get_job_run' id='139851324412688'>.call_count

Example run https://github.com/apache/airflow/actions/runs/13044119066

We can just make it more dynamic by expecting the max calls and asserting that we have finished sooner.

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[potiuk]

nice!