Add tests for building a User from an auth hash
user
```ruby
require 'test_helper'

describe User do

  let(:auth_hash) {
    {
      provider: 'google',
      uid: '12345',
      info: {
        name: 'Stub User',
        email: 'stub.user@example.org',
        image: 'http://example.org/image.jpg',
      }
    }
  }

  it 'can be created from an auth hash' do
    user = User.find_or_create_from_auth_hash(auth_hash)

    assert_equal 'Stub User', user.name
    assert_equal 'stub.user@example.org', user.email
    assert_equal 'google', user.provider
    assert_equal '12345', user.provider_uid
    assert_equal 'http://example.org/image.jpg', user.image_url
  end

  it 'can be found from a matching email' do
    existing_user = create(:user, email: auth_hash[:info][:email])
    user = User.find_or_create_from_auth_hash(auth_hash)

    assert_equal existing_user.id, user.id
  end

  it 'updates the user details on sign in' do
    existing_user = create(:user, email: auth_hash[:info][:email],
                                  name: 'Another Name')
    User.find_or_create_from_auth_hash(auth_hash)

    existing_user.reload
    assert_equal 'Stub User', existing_user.name
  end
  
end
```
assistant