instead of looking linked user by email because :
- follows FC recommendation to fetch ds account by openid
- the email is not a valid key as many user can share the same FCI email.
The following scenario is now working
A user A (email: 1@mail.com) uses FC to connect to DS
=> It is connected as 1@mail.com
Another user B (email: generic@mail.com) uses FC to connect
=> It is connected as generic@mail.com
The first user A change its FC email to generic@mail.com and connect to DS
=> It is still connected as 1@mail.com
Test helpers are separated between two files: spec_helper and
rails_helper. This separation is meant to allow tests that do not
require Rails (like testing standalone libs) to boot faster.
The spec_helper file is always loaded, through `--require spec_helper`
in the `.rspec` config file. When needed, the rails_helper file is
expected to be required manually.
This is fine, but:
- Many test files have a redundant `require 'spec_helper'` line;
- Many test files should require `rails_helper`, but don't.
Not requiring `rails_helper` will cause the Rails-concerned section of
the test environment not to be configured–which may cause subtle bugs
(like the test database not being properly initialized).
Moreover, Spring loads all the Rails files on preloading anyway. So the
gains from using only `spec_helper` are thin.
To streamline this process, this commit:
- Configures `.rspec` to require `rails_helper` by default;
- Remove all manual requires to spec_helper or rails_helper.
Reference: https://stackoverflow.com/questions/24145329/how-is-spec-rails-helper-rb-different-from-spec-spec-helper-rb-do-i-need-it
