hypervisor: fix CH network test initializer pci_path field

Set the new pci_path field in cloud-hypervisor network test config so
unit tests compile with the updated NetworkConfig struct.

Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Assisted-by: OpenAI Codex <codex@openai.com>

src/runtime-rs/crates/hypervisor/src/ch/inner_device.rs

@@ -571,6 +571,7 @@ mod tests {
             allow_duplicate_mac: false,
             use_generic_irq: None,
             use_shared_irq: None,
+            pci_path: None,
         };
 
         let net = NetConfig::try_from(cfg.clone());