Direct Dependencies for Multi-Module Projects

### Current Behavior

Currently there is a flag to filter "direct only" dependencies in the UI.

We have several projects which are multi-module in Gradle, when we flag this "direct only" we simply see the modules of the multi-module.

### Proposed Behavior

I would love to see that with "direct only" (or a smiliar filter) we see the direct dependencies of all sub-modules.

### Checklist

- [x] I have read and understand the [contributing guidelines](https://github.com/DependencyTrack/dependency-track/blob/master/CONTRIBUTING.md#filing-issues)
- [x] I have checked the [existing issues](https://github.com/DependencyTrack/dependency-track/issues) for whether this enhancement was already requested