Add hidden file check to integration tests

test/integration/docker/deployer/app/Dockerfile

@@ -5,4 +5,5 @@ COPY default.conf /etc/nginx/conf.d/default.conf
 ARG COMMIT_SHA
 RUN echo $COMMIT_SHA > /usr/share/nginx/html/version
 RUN mkdir -p /usr/share/nginx/html/versions && echo "version" > /usr/share/nginx/html/versions/$COMMIT_SHA
+RUN mkdir -p /usr/share/nginx/html/versions && echo "hidden" > /usr/share/nginx/html/versions/.hidden
 

test/integration/main_test.rb

@@ -76,5 +76,7 @@ class MainTest < IntegrationTest
       versions.each do |version|
         assert_equal "200", Net::HTTP.get_response(URI.parse("http://localhost:12345/versions/#{version}")).code
       end
+
+      assert_equal "200", Net::HTTP.get_response(URI.parse("http://localhost:12345/versions/.hidden")).code
     end
 end