Add some pause before the beginning of each test to let Minio start

src/minio_test_server.rs

@@ -51,6 +51,7 @@ impl MinioTestServer {
         };
 
         // Wait for Minio to become ready
+        std::thread::sleep(Duration::from_millis(500));
         let mut check_count = 0;
         loop {
             if check_count >= 100 {