Modify Milvus hosting resource to use generated password by default

[timheuer]

Is there an existing issue for this?

• [x] I have searched the existing issues

Describe the bug

Miluvs changed to support config-based password default (instead of global default) (see: https://github.com/milvus-io/milvus/issues/33058). This bug tracks modifying reacting to that change in the Aspire.Hosting.Milvus package to enable a generated default password if none provided, similar to other resources. This will only work on a later tagged image of the milvus container image. /cc @eerhardt

[Alirexaa]

Milvus 2.4.7 was released recently, we should cover this issue in 8.2