transport/quic: Remove default feature

See libp2p#2918.

transports/quic/Cargo.toml

@@ -9,7 +9,7 @@ license = "MIT"
 
 [dependencies]
 async-std-crate = { package = "async-std", version = "1.12.0", default-features = false, optional = true }
-async-trait = "0.1.50"
+bytes = "1.2.1"
 futures = "0.3.15"
 futures-timer = "3.0.2"
 if-watch = "2.0.0"
@@ -28,12 +28,12 @@ x509-parser = "0.13.0"
 yasna = "0.5.0"
 
 [features]
-default = ["async-std"]
 tokio = ["tokio-crate"]
 async-std = ["async-std-crate"]
 
 [dev-dependencies]
 async-std-crate = { package = "async-std", version = "1.12.0", features = ["attributes"] }
+async-trait = "0.1.50"
 libp2p = { version = "0.49.0", default-features = false, features = ["request-response"], path = "../.." }
 rand = "0.8.4"
 tokio-crate = { package = "tokio", version = "1.21.1", features = ["macros", "rt-multi-thread"] }