Use the rt-threaded feature to take advantage of all cores, and bump to the latest version of warp (#5762)

frameworks/Rust/warp-rust/Cargo.toml

@@ -8,6 +8,6 @@ edition = "2018"
 futures = "0.3.1"
 rand = "0.7.3"
 serde = { version = "1.0.103", features = ["derive"] }
-tokio = { version = "0.2.9", features = ["macros"] }
+tokio = { version = "0.2.21", features = ["macros", "rt-threaded"] }
 tokio-postgres = "0.5.1"
-warp = "0.2.0"
+warp = "0.2.3"