[IP2WS2324G2-178] Update User Fronted logic

• Created getUserData() and saveChanges() in updateprofile.component.ts
• Created updateUser() in profile.component.ts
• Created editUser() in user.service.ts

Unit Tests

Nr	Test	Expectation
1	User leaves one of these input fields empty (eMail, username, firstname, lastname)	Error
2	User adds main emphasis, goals and interests (Use break lines, if you type more values in each input field)	Success
3	User leaves one of the input fields main emphasis, goals and interests empty	Success
4	User edits all their data	Success