fix(amazon): Support AWS China region endpoints in RedshiftSQLHook OpenLineage identifier parsing

[jun09]

What

Fix _get_identifier_from_hostname in RedshiftSQLHook to correctly parse AWS China region endpoints (amazonaws.com.cn).

Why

AWS China regions (cn-north-1, cn-northwest-1) use a different endpoint suffix than global regions:

Region	Endpoint format	Parts
Global	my-cluster.id.us-east-1.redshift.amazonaws.com	6
China	my-cluster.id.cn-north-1.redshift.amazonaws.com.cn	7

The existing code only checks hostname.endswith("amazonaws.com") and len(parts) == 6, which fails for China endpoints. This causes the OpenLineage authority to fall back to the raw hostname instead of the expected cluster_identifier.region_name format.

Affects both provisioned clusters and Redshift Serverless workgroups in China regions.

How

Added a check for amazonaws.com.cn with len(parts) == 7, using the same parsing logic (parts[0].parts[2]) since the cluster identifier and region are at the same positions.

Testing

Added two parametrized test cases covering:

• Provisioned cluster in cn-north-1
• Redshift Serverless workgroup in cn-northwest-1

Verified with a real Redshift Serverless endpoint in cn-north-1:
airflow-test.029295324148.cn-north-1.redshift-serverless.amazonaws.com.cn

[boring-cyborg]

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[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.