Handle Guest login

[mirmahathir1]

Our app supports a guest mode where we simulate the app using dummy data. This guest mode will help you showcase what you did to other people without necessarily giving them credentials.
Please add a 'guest' support feature to your UI.

Specifications:

• Modify your URL to take on an extra boolean query parameter 'guest' as follows:
  https://badhan-datainput.netlify.app/#/home?token=blahblahblah&guest=true
  The 'guest' flag will denote whether the site is being accessed by a guest.
• If the site is being accessed as a guest, populate dummy user information in the side drawer and the token in the query will be completely ignored
• the button for uploading an excel file will not prompt a file upload window to appear; rather- some dummy data will be populated in the UI directly
• Call the following dummy route of the API for simulating the POST /donors api call
  POST https://badhan-web-test.herokuapp.com/guest/donors
  (accessing the dummy route doesn't require any authentication nor any proper JSON body)