Fix

Author: Hardvan

src/test/java/com/thealgorithms/stacks/PostfixEvaluatorTest.java

@@ -3,9 +3,8 @@
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
-import org.junit.jupiter.api.Test;
-
 import java.util.EmptyStackException;
+import org.junit.jupiter.api.Test;
 
 public class PostfixEvaluatorTest {