[#144502159] [#38] [Refactor] Add several testcases file to strengthen unit test

assets/js/ApplicantPage.jsx

assets/js/CreateVacancy.jsx

assets/js/Dashboard.jsx

assets/js/VacancyPage.jsx

assets/js/__test__/ApplicantPage-test.jsx

assets/js/__test__/CreateVacancy-test.jsx

assets/js/__test__/Dashboard-test.jsx

assets/js/__test__/Login.jsx

assets/js/__test__/TranscriptPage-test.jsx

assets/js/__test__/VacancyPage-test.jsx

assets/js/__test__/components/Applicant-test.jsx

assets/js/__test__/components/ApplicantList-test.jsx

assets/js/__test__/components/ApproveModal-test.jsx

assets/js/__test__/components/TopMenu-test.jsx

assets/js/__test__/components/Vacancy-test.jsx

assets/js/__test__/components/VacancyList-test.jsx

assets/js/components/Applicant.jsx

assets/js/components/ApplyModal.jsx

assets/js/components/ApproveModal.jsx

assets/js/components/CompanyRegisterModal.jsx