更新 test_install.rs

Author: zhw2101024

tests/by-util/test_install.rs

@@ -1772,8 +1772,7 @@ fn test_install_failing_copy_file_to_target_contain_subdir_with_same_name() {
     let dir1 = "dir1";
 
     at.touch(file);
-    at.mkdir(dir1);
-    at.mkdir(format!("{}/{}", dir1, file));
+    at.mkdir_all(&format!("{dir1}/{file}"));
     ucmd.arg(file)
         .arg(dir1)
         .fails()