Merge pull request rubyforgood#1380 from rubyforgood/supervisor_diges…

…t_fix

Fix typo

lib/tasks/send_supervisor_digest.rake

@@ -1,6 +1,6 @@
 desc "Send an email to supervisors each week to share an overview of their volunteers' activities"
 task send_supervisor_digest: :environment do
-  Supervisor.each do |supervisor|
+  Supervisor.find_each do |supervisor|
     SupervisorMailer.weekly_digest(supervisor)
   end
 end