nix_rs: FlakeUrl: Add *Ord instance

crates/nix_rs/src/flake/url.rs

@@ -15,7 +15,7 @@ use serde::{Deserialize, Serialize};
 ///
 /// Use `FromStr` to parse a string into a `FlakeUrl`. Or `From` or `Into` if
 /// you know the URL is valid.
-#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
 pub struct FlakeUrl(pub String);
 
 impl FlakeUrl {