Address some minor Clippy complaints.

src/network/standard.rs

@@ -21,6 +21,12 @@ impl Builtin {
     }
 }
 
+impl Default for Builtin {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 macro_rules! local_address_impl {
     ($t: ty) => {
        impl HasLocalAddress for $t {
@@ -182,7 +188,6 @@ fn check_sanity() {
     let listener_task_handle = async_std::task::spawn(async move {
         let (mut stream, addr, port) = listener.accept().await.expect("Didn't get connection");
         let mut result_buffer = [0u8; 4];
-        println!("Starting read!");
         stream
             .read_exact(&mut result_buffer)
             .await

src/server.rs

@@ -123,7 +123,7 @@ async fn run_authentication(
         Ok(cg)
             if cg
                 .acceptable_methods
-                .contains(&&AuthenticationMethod::UsernameAndPassword)
+                .contains(&AuthenticationMethod::UsernameAndPassword)
                 && params.check_password.is_some() =>
         {
             match ClientUsernamePassword::read(Pin::new(&mut stream)).await {
@@ -147,7 +147,7 @@ async fn run_authentication(
 
         // and, in the worst case, we'll see if our user is cool with unauthenticated connections
         Ok(cg)
-            if cg.acceptable_methods.contains(&&AuthenticationMethod::None)
+            if cg.acceptable_methods.contains(&AuthenticationMethod::None)
                 && params.allow_unauthenticated =>
         {
             Some(stream)