amethyst: follow the paperclip (clippys) advice

src/builder/paccache.rs

@@ -39,7 +39,7 @@ impl PaccacheBuilder {
         }
 
         command
-            .args(&["-r", &format!("-k{}", self.keep.to_string())])
+            .args(&["-r", &format!("-k{}", self.keep)])
             .wait_success()
             .await
     }

src/operations/clean.rs

@@ -57,7 +57,7 @@ pub async fn clean(options: Options) {
             .uninstall()
             .await;
 
-        if let Err(_) = result {
+        if result.is_err() {
             crash!(AppExitCode::PacmanError, "Failed to remove orphans");
         } else {
             tracing::info!("Successfully removed orphans");

src/operations/upgrade.rs

@@ -33,7 +33,7 @@ async fn upgrade_repo(options: Options) {
         .upgrade()
         .await;
 
-    if let Err(_) = result {
+    if result.is_err() {
         let continue_upgrading = prompt!(default no,
             "Failed to upgrade repo packages, continue to upgrading AUR packages?",
         );