Feature/demo user

[TawfiqKhan]

What this PR does

• Show a welcome image on the left on the login/signup page
• created a demo user login button.

Screenshot

Any information needed to test this feature (required):

• Create an account using email 'demo@demo.com' and password 'test12345'

Any issues with the current functionality (optional):

• It is responsive on smaller screens but components alignments can be improved
• position of the image on medium and smaller screen can be adjusted