fix(job): Cron::WeeklyOverviewJob simplified and respect dolist API rate limiting

app/jobs/cron/weekly_overview_job.rb

@@ -1,13 +1,16 @@
 class Cron::WeeklyOverviewJob < Cron::CronJob
   self.schedule_expression = "every monday at 7 am"
 
-  def perform(*args)
+  def perform
     # Feature flipped to avoid mails in staging due to unprocessed dossier
-    if Rails.application.config.ds_weekly_overview
-      Instructeur.all
-        .map { |instructeur| [instructeur, instructeur.last_week_overview] }
-        .reject { |_, overview| overview.nil? }
-        .each { |instructeur, _| InstructeurMailer.last_week_overview(instructeur).deliver_later }
+    return unless Rails.application.config.ds_weekly_overview
+
+    Instructeur.find_each do |instructeur|
+      # NOTE: it's not exactly accurate because rate limit is not shared between jobs processes
+      Dolist::API.sleep_until_limit_reset if Dolist::API.near_rate_limit?
+
+      # mailer won't send anything if overview if empty
+      InstructeurMailer.last_week_overview(instructeur)&.deliver_later
     end
   end
 end