feature request: Redis config no way to select redis database

What problem did you meet?

In Logto v1.42.0, when using Redis there's no way to specify which Redis database (DB index) to use — even adding /1 to the connection parameter doesn't take effect. It would be great if the next version could support specifying the Redis database.eg:redis://:password@Redis/1

Describe what you'd like Logto to have

In Logto v1.42.0, when using Redis there's no way to specify which Redis database (DB index) to use — even adding /1 to the connection parameter doesn't take effect. It would be great if the next version could support specifying the Redis database.eg:redis://:password@Redis/1