Update needed for Rust v1.77.0

Bug: http://b/330185853

Test: ./test_compiler.py --prebuilt-path dist/rust-dev.tar.xz  --target aosp_cf_x86_64_phone --image
Change-Id: I22a1ad28f26c99e7e766e677b4cf13bc340bf95d
diff --git a/service_vm/manager/src/lib.rs b/service_vm/manager/src/lib.rs
index 8dedec5..44c7871 100644
--- a/service_vm/manager/src/lib.rs
+++ b/service_vm/manager/src/lib.rs
@@ -225,6 +225,7 @@
     }
     let instance_img = OpenOptions::new()
         .create(true)
+        .truncate(true)
         .read(true)
         .write(true)
         .open(instance_img_path)