步骤 1：先设置为 preferred 模式
aws elasticache modify-replication-group \
--replication-group-id test \
--transit-encryption-mode preferred \
--apply-immediately
步骤 2
等待修改完成
步骤 3：禁用 TLS
aws elasticache modify-replication-group \
--replication-group-id test \
--no-transit-encryption-enabled \
--apply-immediately
