refactor: create_output func

Author: ananasmoe

src/image.rs

@@ -44,14 +44,12 @@ impl Image {
         let model = &options.model.clone().unwrap();
         let extension = &options.output_ext.to_string().to_lowercase();
 
-        let out = format!(
+        format!(
             "{}_{}_x{}.{}", 
             self.path.file_stem().unwrap().to_string_lossy(), 
             model.name, 
             &options.scale,
             extension
-        );
-
-        out
+        )
     }
 }