PYSEC-2026-595

In the AWS Secrets Manager and SSM Parameter Store secrets backends of `apache-airflow-providers-amazon` prior to 9.28.0, the team-scoping logic could resolve a `conn_id` containing a `/` (e.g. `"my_team/conn"`) to the same path as another team's team-scoped secret when the caller had no team context. A privileged caller without team context could therefore retrieve another team's secret by crafting a colliding `conn_id`. Fixed in 9.28.0 by switching the team-scope separator to `--` and rejecting team-shaped `conn_id`s when team context is absent. Affects the experimental multi-tenant teams feature only. Users are recommended to upgrade to `apache-airflow-providers-amazon` 9.28.0, which fixes the issue.