Add open_timeout (#2555)

app/helpers/application_helper.rb

@@ -111,6 +111,7 @@ module ApplicationHelper
     http = Net::HTTP.new(url.host, url.port)
     http.use_ssl = (url.scheme == "https")
     http.read_timeout = 10
+    http.open_timeout = 10
 
     http.start do |web|
       response = web.head(url.request_uri)