Extract component for remote translations button

So we're consistent with the rest of the code in the header, which
renders components and not partials.

app/components/layout/remote_translations_button_component.html.erb

@@ -0,0 +1,11 @@
+<div class="remote-translations-button callout primary text-center">
+  <% if display_remote_translation_button? %>
+    <%= form_tag remote_translations_path do %>
+      <%= hidden_field_tag :remote_translations, remote_translations.to_json %>
+      <%= t("remote_translations.text") %>
+      <%= submit_tag t("remote_translations.button") %>
+    <% end %>
+  <% else %>
+    <%= t("remote_translations.all_remote_translations_enqueued_text") %>
+  <% end %>
+</div>

app/components/layout/remote_translations_button_component.rb

@@ -0,0 +1,20 @@
+class Layout::RemoteTranslationsButtonComponent < ApplicationComponent
+  attr_reader :remote_translations
+
+  def initialize(remote_translations)
+    @remote_translations = remote_translations
+  end
+
+  def render?
+    remote_translations.present? &&
+      RemoteTranslations::Microsoft::AvailableLocales.include_locale?(I18n.locale)
+  end
+
+  private
+
+    def display_remote_translation_button?
+      remote_translations.none? do |remote_translation|
+        RemoteTranslation.remote_translation_enqueued?(remote_translation)
+      end
+    end
+end