Merge pull request #5163 from coopdevs/collect-Ruby-GC

Enable Ruby Runtime Metrics in Datadog

config/initializers/datadog.rb

@@ -4,5 +4,6 @@ if ENV['DATADOG_RAILS_APM']
     c.use :delayed_job, service_name: 'delayed_job'
     c.use :dalli, service_name: 'memcached'
     c.analytics_enabled = true
+    c.runtime_metrics_enabled = true
   end
 end