[test] example timestamp uefi_services change to uefi::helpers

Author: sky5454

uefi-test-runner/examples/timestamp.rs

@@ -19,7 +19,7 @@ use uefi::proto::misc::Timestamp;
 fn main(image_handle: Handle, mut system_table: SystemTable<Boot>) -> Status {
     // ANCHOR_END: entry
     // ANCHOR: services
-    uefi_services::init(&mut system_table).unwrap();
+    uefi::helpers::init(&mut system_table).unwrap();
     let boot_services = system_table.boot_services();
     // ANCHOR_END: services