Flaky specs: Localization Changing the locale and Available locales appear in the locale switcher

[javierm]

What

Tests that fail randomly are called "flakies", this one seems to be one:

Travis failed build: https://travis-ci.org/consul/consul/jobs/425725629 Not available anymore.

To reproduce locally, run:

bin/rspec spec/customization_engine_spec.rb:19 spec/features/localization_spec.rb:42 spec/features/localization_spec.rb:32 spec/features/localization_spec.rb:18 --seed 26791

Failure:

  1) Localization Changing the locale
     Failure/Error: select('Español', from: 'locale-switcher')
     
     Capybara::ElementNotFound:
       Unable to find visible option "Español" within #<Capybara::Node::Element tag="select" path="/html/body/div[1]/header/div[1]/div/div[1]/form/select">
     # ./spec/features/localization_spec.rb:36:in `block (2 levels) in <top (required)>'

  2) Localization Available locales appear in the locale switcher
     Failure/Error: expect(page).to have_content 'Español'
       expected to find text "Español" in "English translation missing: es.locale translation missing: fr.locale English translation missing: pt-BR.locale translation missing: val.locale How to help"
     # ./spec/features/localization_spec.rb:22:in `block (3 levels) in <top (required)>'
     # ./spec/features/localization_spec.rb:21:in `block (2 levels) in <top (required)>'

How

• Explain why the test is flaky, or under which conditions/scenario it fails randomly
• Explain why your PR fixes it
• Create a backport PR to consul/consul when the fixing PR is approved

Notes

These failures seem to be related to the way the first test excecutes I18n.load_path = path; I18n.reload! and the second one stubs I18n.available_locales. Those two things combined make the other tests fail because they cause I18n.t("locale", locale: :es) to return "translation missing: es.locale".