Update crates/core/tests/test_merge.rs

Co-authored-by: ValuedMammal <[email protected]>

crates/core/tests/test_merge.rs

@@ -62,7 +62,7 @@ fn test_is_empty() {
     assert!(set.is_empty());
 
     let vec: Vec<i32> = Vec::new();
-    assert!(vec.is_empty());
+    assert!(Merge::is_empty(&vec);
 }
 
 #[test]