Fix DbtCloudRunJobTrigger timeout error message and add final status check

[Vamsi-klu]

Problem

DbtCloudRunJobTrigger.run() has two bugs that surface when a dbt Cloud job run exceeds the configured timeout (#61979):

1. Misleading error message: The timeout error message prints the raw Unix epoch timestamp (self.end_time) instead of a meaningful value, producing nonsensical messages like "Job run 70403194297680 has not reached a terminal status after 1771200015.8 seconds." (≈ 56 years).

2. Missing final status check: When the timeout fires, the trigger immediately yields an error without re-checking whether the job has since completed. If a job finishes between the last poll and the timeout boundary, Airflow incorrectly reports a timeout failure even though the dbt Cloud job succeeded.

Solution

• Bug 1: Changed the error message from f"after {self.end_time} seconds." to f"within the configured timeout." since self.end_time is an absolute epoch timestamp, not a relative duration.

• Bug 2: Added a final is_still_running() check before yielding the timeout error. If the job completed in the interim, the trigger breaks out of the while loop and falls through to the normal terminal status handling (success/cancelled/error).

Testing Done

• Updated existing test_dbt_job_run_timeout to verify the corrected error message format.
• Added new test_dbt_job_run_timeout_with_final_status_check test that simulates a job completing at the timeout boundary — verifies the trigger yields success instead of a false timeout error.
• All 11 tests in providers/dbt/cloud/tests/unit/dbt/cloud/triggers/test_dbt.py pass.
• Ruff lint and format checks pass.

Breaking Changes

None. The only user-visible change is the timeout error message text, which previously contained an incorrect value (epoch timestamp) and now says "within the configured timeout." instead.

Closes: #61979

🤖 Generated with Claude Code

[Vamsi-klu]

cc @jscheffl @josh-fell @potiuk — Would appreciate a review on this fix for the dbt-cloud provider trigger timeout bugs reported in #61979. The changes are small and focused:

1. Fixed the misleading timeout error message (was printing a Unix epoch timestamp as seconds)
2. Added a final is_still_running() check before declaring timeout to prevent false failures

All existing tests pass plus one new test for the race-condition fix.

[Vamsi-klu]

Collaborators for this PR: @codingrealitylabs and @girlcoder-gaming. They helped me raise this PR.