[Request]: Support loading network configuration from file

### Feature or enhancement request details

Today our network plugin will take in a set of parameters for configuring the network we're trying to make. Instead, we could load the network configuration from a fixed path in the container bundle. This would allow us to be more flexible in what options we send to different network plugins.

### Code of Conduct

- [x] I agree to follow this project's Code of Conduct

Start by tracing how the network plugin currently receives its configuration parameters and how the container bundle exposes files. Determine the fixed configuration path and expected format from the existing plugin flow. Done means network configuration can be loaded from that path and used to provide options to different network plugins.

Written by the indexing model from the issue text.