Stop relying on unstructured data in network performance KPI codebase

**What would you like to be added**:

Instead of operating on Unstructured items, we want to define our type the same way built-in APIs are defined,
Example:
https://github.com/kubernetes/sample-controller/blob/master/pkg/apis/samplecontroller/v1alpha1/types.go

In network_performance_measurement.go , we have a CR NetworkTestRequest update events being received.
These objects need to be handled using defined types , but instead of unstructured items.

**Why is this needed**:

Operating on unstructured (if not needed), isn't a good pattern - this code would be much simpler if operating on the type itself.

Start with network_performance_measurement.go and inspect how NetworkTestRequest update events are currently received and handled as unstructured items. Compare the type definitions and event-handling approach in the linked sample-controller types.go. Done means NetworkTestRequest uses defined API types instead of unstructured items throughout this flow.

Written by the indexing model from the issue text.