Add a check for the running version

[fabioperrella]

In Heartcheck there is the check watch_file which can be used to know if the running version is the same as the files that exist in the filesystem, like this:

monitor.add :watch_file do |config|
  config.name = 'version'
  config.add_service(file: Rails.root.join('version.json'))
end

I think there could be a similar check for Sidekiq because it runs in a different process than the web one, so it is not covered by the check above.