Stop retrying tests three times if qunit tests fail

Warming up the Rails server should be enough

lib/tasks/qunit.rake

@@ -86,16 +86,7 @@ task "qunit:test", [:timeout, :qunit_path] => :environment do |_, args|
     end
     puts "Rails server is warmed up"
 
-    # wait for server to respond, will exception out on failure
-    tries = 0
-    begin
-      sh(cmd)
-    rescue
-      exit if ENV['RETRY'].present? && ENV['RETRY'] == 'false'
-      sleep 2
-      tries += 1
-      retry unless tries == 3
-    end
+    sh(cmd)
 
     # A bit of a hack until we can figure this out on Travis
     tries = 0