Salvo: upgrade to 0.31 (#20)

Author: chrislearn

benchmark/hello-world/salvo/Cargo.toml

@@ -6,5 +6,5 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-salvo = "0.25"
+salvo = "0.31"
 tokio = { version = "1.12", features = ["rt-multi-thread", "macros"] }

benchmark/hello-world/salvo/src/main.rs

@@ -1,6 +1,6 @@
 use salvo::prelude::*;
 
-#[fn_handler]
+#[handler]
 fn hello() -> &'static str {
     "Hello, World!"
 }