Apache Airflow: Incomplete Redaction of Sensitive Fields in Connection Extra API Response

A bug in the GET `/api/v2/connections/{connection_id}` REST API endpoint in Apache Airflow allowed an authenticated UI/API user with Connection-read permission to retrieve secrets stored in a Connection's `extra` JSON blob under field names not present in the redaction allowlist (`DEFAULT_SENSITIVE_FIELDS`) — for example, official Slack-provider credential field names were returned in plaintext. Affects deployments that store credentials in Connection `extra` blobs and grant Connection-read access to multiple users. Users are advised to upgrade to `apache-airflow` 3.2.2 or later. As a defense-in-depth mitigation, deployment operators can store sensitive credential values in a secret-backend rather than inlined into the Connection's `extra` field.