fix: ExceptionNotifier is unavailable/unknown

Author: salzig

lib/tasks/scheduler.rake

@@ -31,7 +31,7 @@ namespace :scheduler do
   def with_tracking
     yield
   rescue StandardError => e
-    ExceptionNotifier.notify_exception(e) if Rails.env.production?
+    Appsignal.report_error(e) if Rails.env.production?
     Rails.logger.error("exception during task invocation: #{e}\n#{e.backtrace.join("\n")}")
   end
 end