Disable log_arguments for AnalyticsJobs

For Rails 6.0, which doesn't support this, turn of :info logging
altogether.

lib/dfe/analytics/railtie.rb

@@ -13,6 +13,19 @@ class Railtie < Rails::Railtie
         app.config.middleware.use DfE::Analytics::Middleware::RequestIdentity
       end
 
+      initializer 'dfe.analytics.logger' do
+        ActiveSupport.on_load(:active_job) do
+          analytics_job = DfE::Analytics::AnalyticsJob
+          # Rails < 6.1 doesn't support log_arguments = false so we only log warn
+          # to prevent wild log inflation
+          if analytics_job.respond_to?(:log_arguments=)
+            analytics_job.log_arguments = false
+          else
+            analytics_job.logger = ::Rails.logger.dup.tap { |l| l.level = Logger::WARN }
+          end
+        end
+      end
+
       config.after_initialize do
         # internal gem tests will sometimes suppress this so they can test the
         # init process

lib/dfe/analytics/send_events.rb

@@ -13,6 +13,7 @@ def self.do(events)
 
       def perform(events)
         if DfE::Analytics.log_only?
+          # Use the Rails logger here as the job's logger is set to :warn by default
           Rails.logger.info("DfE::Analytics: #{events.inspect}")
         else
           response = DfE::Analytics.events_client.insert(events, ignore_unknown: true)