style: remove redundant import to fix checkstyle error

Author: priyanshuvishwakarma273403

src/test/java/com/thealgorithms/datastructures/lists/PalindromeSinglyLinkedListTest.java

@@ -2,8 +2,6 @@
 
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
-
-import com.thealgorithms.datastructures.lists.SinglyLinkedList;
 import org.junit.jupiter.api.Test;
 
 public class PalindromeSinglyLinkedListTest {