Anonymous sign in

[ashritaraman]

Summary
This pull request supports Anonymous sign in through Firebase so that users don't have to sign in through Google. This will hopefully fix the issue with Apple where we were required to add Apple sign-in if we had Google sign-in in order to push to the app store.

How it works now

• When the user presses 'get started,' a getStarted method is triggered where the user is signed in anonymously and an id is generated.
• That Id is passed into the get server auth token, which validates the anonymous token and returns another token generated by Django.
• The new Django token is what will be used for authentication.
• In order to implement these changes, I had to update the API key (the other one was expired) and enable the Identity Toolkit API in the google developer console.

Test Plan
-Test plan is to run the backend server and see if a servertoken is appropriately generated.

Breaking Changes
-Users will not be using google sign in

[dti-github-bot]

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