Tests: Add tests for checking input validations on Register form.

[Aaishpra]

Describe the solution you'd like

• Assert if validation check pops up for empty username or email.
• Assert if validation check pops up if the password and email are not in correct format.
• Assert if validation check pops up if passwords are not same

Describe any other information required

Use jest for testing . More info on testing https://jestjs.io/docs/tutorial-react

Additional context

This can be useful.

[jennypoon]

I would like to give this a shot

[isabelcosta]

Thank you so much for creating this @Aaishpra 🙌🏾 I assigned it to you @jennypoon :)