Resolve mem_replace_with_default clippy lint

    warning: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
      --> serde_derive/src/internals/receiver.rs:52:24
       |
    52 |         let segments = mem::replace(&mut path.segments, Punctuated::new());
       |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut path.segments)`
       |
       = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#mem_replace_with_default
       = note: `-W clippy::mem-replace-with-default` implied by `-W clippy::all`
       = help: to override `-W clippy::all` add `#[allow(clippy::mem_replace_with_default)]`

Author: dtolnay

serde_derive/src/internals/receiver.rs

@@ -49,7 +49,7 @@ impl ReplaceReceiver<'_> {
 
         path.leading_colon = Some(**path.segments.pairs().next().unwrap().punct().unwrap());
 
-        let segments = mem::replace(&mut path.segments, Punctuated::new());
+        let segments = mem::take(&mut path.segments);
         path.segments = segments.into_pairs().skip(1).collect();
     }