BURs: don't automatically retry failed BURs.

If a bulk update job fails, don't automatically retry it. Retrying it
will clobber the original error message if it fails again.

app/jobs/bigquery_export_job.rb

@@ -5,6 +5,11 @@
 class BigqueryExportJob < ApplicationJob
   retry_on Exception, attempts: 0
 
+  # XXX delayed_job specific
+  def max_attempts
+    1
+  end
+
   def perform(model:, **options)
     BigqueryExportService.new(model, **options).export!
   end

app/jobs/discord_notification_job.rb

@@ -3,6 +3,11 @@
 class DiscordNotificationJob < ApplicationJob
   retry_on Exception, attempts: 0
 
+  # XXX delayed_job specific
+  def max_attempts
+    1
+  end
+
   def perform(forum_post:)
     forum_post.send_discord_notification
   end

app/jobs/process_bulk_update_request_job.rb

@@ -5,6 +5,11 @@
 class ProcessBulkUpdateRequestJob < ApplicationJob
   retry_on Exception, attempts: 0
 
+  # XXX delayed_job specific
+  def max_attempts
+    1
+  end
+
   def perform(bulk_update_request)
     bulk_update_request.processor.process!
   end