Remove redundant imports

src/routes/user.rs

@@ -9,7 +9,6 @@ use rocket::{
     response::{status, Content, Flash, Redirect},
 };
 use rocket_i18n::I18n;
-use serde_json;
 use std::{borrow::Cow, collections::HashMap};
 use tracing::{info, warn};
 use validator::{Validate, ValidationError, ValidationErrors};