Feature/recaptcha verification

[juuso-j]

Recaptcha verification

Description

Trello #76

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Breakdown:

API

1. profiles/api/views.py
   • Add recpatcha verification to start_poll

Tests

1. account/tests/test_api.py
   • Mock recaptcha return value in test_profile_created
2. profiles/tests/api/test_answer.py
   • Move test_poll_start to test_question.py
3. profiles/tests/api/test_question.py
   • Testi recaptcha verification

Other

1. config_dev.env.example
2. mpbackend/settings.py
   • Add google recaptcha environment variables