tests: disable virtio_balloon_free_page_reporting on mshv

balloon_free_page_reporting test case should not
work as expected. The reason is that MSHV pins
all the pages during the memory map for the guest.
Those pages can not be altered without unpinning the pages.
MSHV does not support modifying the pages during the guest
life cycle. This test case can be enabled once we add
VA backed VM support.

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

tests/integration.rs

@@ -5199,6 +5199,7 @@ mod common_parallel {
     }
 
     #[test]
+    #[cfg(not(feature = "mshv"))]
     fn test_virtio_balloon_free_page_reporting() {
         let focal = UbuntuDiskConfig::new(FOCAL_IMAGE_NAME.to_string());
         let guest = Guest::new(Box::new(focal));