refactoring: removed redundant student variable in testPrintStudentInfo()

src/test/java/org/example/StudentTest.java

@@ -72,12 +72,11 @@ class StudentTest {
 
     @Test
     void testPrintStudentInfo() {
-        Student student = sampleStudent;
 
         ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
         System.setOut(new PrintStream(outputStream));
 
-        student.printStudentInfo();
+        sampleStudent.printStudentInfo();
 
         String printedOutput = outputStream.toString().trim();