chore: resolve clippy warnings for pre-push audit

server/tests/image_test.rs

@@ -1,7 +1,6 @@
-use image::DynamicImage;
 #[test]
 fn test_img() {
     let mut img = image::DynamicImage::new_rgb8(10, 10);
     img.invert();
-    let img2 = img.adjust_contrast(20.0);
+    let _img2 = img.adjust_contrast(20.0);
 }