Review Fix: Handle Empty Payslip History

<SRS> SRS02: Employee Management </SRS>

<Changes>
 - Enhanced viewPayslipHistory() in MenuHelper.h to handle empty payslip scenarios.
 - Displayed "No Payslips Generated" message when no records exist.
</Changes>

<Review>
  Smitha Mohan
</Review>

Trenser.Zenvy/Trenser.Zenvy/views/MenuHelper.h

@@ -22,6 +22,12 @@ inline void viewPayslipHistory(std::shared_ptr<ZenvyController> controller)
 {
     auto employeePayslips = controller->getCurrentEmployee()->getEmployeePayslips();
     util::clear();
+    if (employeePayslips.empty()) 
+    {
+        std::cout << "No Payslips Generated";
+        util::pressEnter();
+        return;
+    }
     std::cout << "Payslips\n" << std::endl;
     std::cout << std::left
         << std::setw(15) << "Date"