Ensure all containers are password protected

Where possible, we should be enabling passwords on our containers.

The goal here is to provide a layer of redundancy. If ACA firewalling (or other system to from external access) fails, an external client will still not be able to access the container without knowledge of the authentication password.

The following containers don't have password protection:

- [x] Garnet (https://github.com/dotnet/aspire/pull/7618)
- [ ] Kafka
- [x] MongoDB (https://github.com/dotnet/aspire/pull/5788)
- [x] Nats (https://github.com/dotnet/aspire/pull/6259)
- [x] Redis (https://github.com/dotnet/aspire/issues/3838)
- [x] ~Seq~ See more info on https://github.com/dotnet/aspire/pull/6878
- [x] Valkey (https://github.com/dotnet/aspire/pull/7887)