Attempt to address test failures on CI

spec/support/acceptance/helpers/command_helpers.rb

@@ -39,6 +39,13 @@ module AcceptanceTests
 
     def run_command_within_bundle(*args)
       run_command_isolated_from_bundle(*args) do |runner|
+        bundler_version = `bundle -v`.sub(/Bundler version /, '')
+
+        if bundler_version !~ /^1\./
+          puts 'Installing Bundler 1.x...'
+          system('gem', 'install', 'bundler', '-v', '~> 1')
+        end
+
         runner.command_prefix = 'bundle exec'
         runner.env['BUNDLE_GEMFILE'] = fs.find_in_project('Gemfile').to_s