Fix test setup for devcontainers by configuring hosts

Author: MrSerth

config/environments/test.rb

@@ -74,4 +74,9 @@
 
   # Raise error when a before_action's only/except options reference missing actions.
   config.action_controller.raise_on_missing_callback_actions = true
+
+  # Allow access to the Rails server through the default test host and the Capybara server.
+  # These settings are needed for the devcontainer setup.
+  config.hosts << ActionDispatch::Integration::Session::DEFAULT_HOST
+  config.hosts << "rails-app:#{ENV['CAPYBARA_SERVER_PORT']}" if ENV['CAPYBARA_SERVER_PORT']
 end