tests: Add PCI MSI interrupt test for confidential VMs

Add test_pci_msi to the common_cvm integration test module to
verify that PCI MSI interrupt functionality works correctly in
confidential guest environments.

The test creates an Ubuntu Jammy-based confidential VM using
GuestFactory and delegates to the existing _test_pci_msi helper
to validate MSI interrupts.

Signed-off-by: Muminul Islam <muislam@microsoft.com>

cloud-hypervisor/tests/integration.rs

@@ -14982,4 +14982,12 @@ mod common_cvm {
             .with_cpu(4);
         _test_virtio_queue_affinity(&guest);
     }
+
+    #[test]
+    fn test_pci_msi() {
+        let disk_config = UbuntuDiskConfig::new(JAMMY_IMAGE_NAME.to_string());
+        let guest =
+            GuestFactory::new_confidential_guest_factory().create_guest(Box::new(disk_config));
+        _test_pci_msi(&guest);
+    }
 }