Derive DbtCloudGetJobRunArtifactOperator default file name after rendering

[1fanwang]

run_id, path and output_file_name are template fields, so they are rendered after __init__ runs. When output_file_name was omitted, the constructor built the default from self.run_id and self.path and flattened slashes then — on the un-rendered Jinja expressions. With a templated path, the '/'→'-' replacement ran on the expression, not the resolved path, so a rendered path like a/b/c.json kept its slashes in the file name (Path then wrote into nested directories). Derive the default in execute(), after rendering.

related: #70296

Testing Done

New test_default_output_file_name_uses_rendered_path renders a templated path ({{ params.p }} → path/to/my/manifest.json) and asserts the default name is <run_id>_path-to-my-manifest.json. It fails on the pre-fix source (slashes survive, name is <run_id>_path/to/my/manifest.json) and passes after. TestDbtCloudGetJobRunArtifactOperator: 11 passed. validate_operators_init.py on the operator exits 0.

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Backport failed to create: v3-3-test. View the failure log Run details

Note: As of Merging PRs targeted for Airflow 3.X
the committer who merges the PR is responsible for backporting the PRs that are bug fixes (generally speaking) to the maintenance branches.

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Status	Branch	Result
❌	v3-3-test

You can attempt to backport this manually by running:

cherry_picker 26d3bbb v3-3-test

This should apply the commit to the v3-3-test branch and leave the commit in conflict state marking
the files that need manual conflict resolution.

After you have resolved the conflicts, you can continue the backport process by running:

cherry_picker --continue

If you don't have cherry-picker installed, see the installation guide.