[AF-12] People authentication

[ricardopacheco]

Issue number: resolves #12

Summary 🔴

This PR adds the user authentication feature. Additional add-ons are available in the changelog in version 0.3.1.

Proposed / Possible solution 🔴

We only added the contract and the operation, as it is an action within the user context.

How to test 👮‍♂️

Start the related services, and open the console with the command bin/console. After that:

attributes = {}

AuctionFunCore::Operations::UserContext::AuthenticationOperation.call(attributes) do |result|
  result.success { |user| puts user.to_h }
  result.failure { |failure| puts failure.to_h }
end

To simulate successful authentication, change the hash of the attributes variable so that it meets all contract requirements.

Risks / Impacts 🔴

• None anticipated

Requirements for deployment 🔴

• None anticipated