Fix cargo clippy issues

geneit_backend/src/services/login_token_service.rs

@@ -125,13 +125,13 @@ async fn load_token_info(token: &LoginTokenValue) -> anyhow::Result<Option<Login
     let token = match user_tokens.iter_mut().find(|t| t.key == key) {
         Some(t) => t,
         None => {
-            log::error!("Could not find token for key '{}' (missing token)", key);
+            log::error!("Could not find token for key '{key}' (missing token)");
             return Ok(None);
         }
     };
 
     if token.is_expired() {
-        log::error!("Could not find token for key '{}' (token expired)", key);
+        log::error!("Could not find token for key '{key}' (token expired)");
         return Ok(None);
     }
 
@@ -169,7 +169,7 @@ impl FromRequest for LoginToken {
 
             let token = match load_token_info(&token).await {
                 Err(e) => {
-                    log::error!("Failed to load auth token! {}", e);
+                    log::error!("Failed to load auth token! {e}");
                     return Err(actix_web::error::ErrorPreconditionFailed(
                         "Failed to check auth token!",
                     ));

geneit_backend/src/services/mail_service.rs

@@ -27,7 +27,7 @@ pub async fn send_mail<D: Display>(to: &str, subject: &str, body: D) -> anyhow::
     let mailer = mailer.build();
 
     mailer.send(&email)?;
-    log::debug!("A mail was sent to {} (subject = {})", to, subject);
+    log::debug!("A mail was sent to {to} (subject = {subject})");
 
     Ok(())
 }

geneit_backend/src/services/members_service.rs

@@ -168,7 +168,7 @@ pub mod loop_detection {
             None => false,
             Some(id) => {
                 if curr_stack.contains(id) {
-                    log::debug!("Loop detected! {:?}", curr_stack);
+                    log::debug!("Loop detected! {curr_stack:?}");
                     return true;
                 }