minor: bump clippy version to 1.64 (#769)

Author: kmahar

.evergreen/check-clippy.sh

@@ -6,7 +6,7 @@ source ./.evergreen/configure-rust.sh
 source ./.evergreen/feature-combinations.sh
 
 # Pin clippy to the latest version. This should be updated when new versions of Rust are released.
-CLIPPY_VERSION=1.63.0
+CLIPPY_VERSION=1.64.0
 
 rustup install $CLIPPY_VERSION
 

src/operation/insert/mod.rs

@@ -100,7 +100,7 @@ impl<'a, T: Serialize> OperationWithDefaults for Insert<'a, T> {
 
                     // overwrite old length
                     let new_length = (bytes.len() as i32).to_le_bytes();
-                    (&mut bytes[0..4]).copy_from_slice(&new_length);
+                    bytes[0..4].copy_from_slice(&new_length);
                     doc = RawDocumentBuf::from_bytes(bytes)?;
 
                     Bson::ObjectId(oid)