Run cargo upgrade.

Cargo.toml

@@ -10,10 +10,10 @@ repository = "https://github.com/ditsing/labrpc"
 homepage = "https://github.com/ditsing/labrpc"
 
 [dependencies]
-bytes = "1.0"
+bytes = "1.1"
 crossbeam-channel = "0.5.1"
-futures = { version = "0.3.15", default-features = false, features = ["std"]}
-parking_lot = "0.11.1"
+futures = { version = "0.3.19", default-features = false, features = ["std"]}
+parking_lot = "0.11"
 rand = "0.8.0"
 tokio = { version = "1.7", features = ["macros", "rt-multi-thread", "sync", "time", "parking_lot"] }