feat: add judoscaler gem for heroku autoscaling (#10419)

- add judoscaler gem to allow judoscale use in heroku environments
- This will allow auto scaling for both web and worker dynos across both
standard-1x/2x and performance dynos
- This will scaling in response to queue time rather than response
time(heroku default)
- This also allows you to scale multiple dynos in and out at once,
rather than scaling them one at a time, as is the default.

Ref
----
1. https://judoscale.com/
2. https://devcenter.heroku.com/articles/judoscale

Gemfile

@@ -181,6 +181,9 @@ gem 'reverse_markdown'
 group :production do
   # we dont want request timing out in development while using byebug
   gem 'rack-timeout'
+  # for heroku autoscaling
+  gem 'judoscale-rails', require: false
+  gem 'judoscale-sidekiq', require: false
 end
 
 group :development do