Throw error message if user has no email from firebase

[MichaelDimitras]

If there are multiple users with the same email in Identity Platform for a particular tenant, an authentication attempt to firebase will return a user with an empty email.

On the frontend we display an error message when that happens:
https://github.com/p0-security/app/blob/5237e1a54597dc63258e56566353ad09ecd3e187/frontend/src/components/Login/hook.ts#L301-L306

But on the CLI we had no such check. This PR adds the same check as on the frontend. Now when a user logs in, if they have multiple identities in Identity Platform they will see the message Can not sign in: this user has previously signed in with a different identity provider.\nPlease contact support@p0.dev to enable this user.

login.bug.mov

[MichaelDimitras]

The ticket has the additional goal:

Ideally, our system will automatically update the user profile in identity platform.

I will take a stab at that as a follow-up, now that I have some understanding of the system.

[fabgo]

This test is a little brittle, as any change to the message will cause the test to fail and require update. Is it not sufficient to verify that an exception is thrown?

[MichaelDimitras]

I'm trying to follow what we were already doing in this file.

await expect(login({ org: "test-org" })).rejects.toMatchInlineSnapshot(
    `"Could not find organization"`
);

await expect(login({ org: "test-org" })).rejects.toMatchInlineSnapshot(
    `"Unsupported login for your organization"`
    `"Unsupported login for your organization"`
);

Personally I like expecting on a particular message to ensure we are displaying the correct message to the user. Theoretically a logic change could expose an error with a different message.

[nbrahms]

I think it's fine. It's only a yarn jest -u to update snapshots.