chore: switch Reference to using an actual reference

crates/delta/src/routes/users/fetch_user.rs

@@ -13,7 +13,7 @@ use rocket::{serde::json::Json, State};
 /// Retrieve a user's information.
 #[openapi(tag = "User Information")]
 #[get("/<target>")]
-pub async fn fetch(db: &State<Database>, user: User, target: Reference) -> Result<Json<v0::User>> {
+pub async fn fetch(db: &State<Database>, user: User, target: Reference<'_>) -> Result<Json<v0::User>> {
     if user.id == target.id {
         return Ok(Json(user.into_self(false).await));
     }