CVE-2026-43826: Apache Airflow Providers OpenSearch: OpenSearch task-log handler leaks credentials embedded in the host URL

The OpenSearch logging provider, when configured with a host URL that embeds credentials (for example https://user:password@server.example.com:9200), wrote the full host URL — including the embedded credentials — into task logs. Any user with task-log read permission could harvest the backend credentials. Users are advised to upgrade to apache-airflow-providers-opensearch 1.9.1 or later and, as a defense-in-depth measure, configure the backend credentials via a secret backend rather than embedding them in the [opensearch] host URL.