Handle error prints on stdout when running tests

[chrisma]

Currently, the following errors (omniauth: (hpi) Authentication failure! invalid_credentials encountered) are printed to stdout during testing:

bundle exec rspec                         
........................*......................................................................................................................................................................................*.*..............................................................E, [2019-03-11T13:54:15.298067 #18961] ERROR -- omniauth: (hpi) Authentication failure! invalid_credentials encountered.
.E, [2019-03-11T13:54:15.649210 #18961] ERROR -- omniauth: (hpi) Authentication failure! invalid_credentials encountered.
........................................*...**.................**......................................................................................*.................................................................................................................................................................................................

Most likely caused by the tests in spec/features/sessions/user_sign_in_spec.rb
Edit: Confirmed:

$ bundle exec rspec spec/features/sessions/user_sign_in_spec.rb
...E, [2019-03-11T14:05:14.854728 #19355] ERROR -- omniauth: (hpi) Authentication failure! invalid_credentials encountered.
.E, [2019-03-11T14:05:15.262083 #19355] ERROR -- omniauth: (hpi) Authentication failure! invalid_credentials encountered.
.

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5 examples, 0 failures