added test hash to reviewer email subject line

app/mailers/reviewer_mailer.rb

@@ -4,6 +4,6 @@ class ReviewerMailer < ApplicationMailer
     @candidate = candidate
     recipients = candidate.quiz.reviewers.map(&:email)
 
-    mail to: recipients, subject: "Skills Assessment Results"
+    mail to: recipients, subject: "Skills Assessment Results - #{@candidate.test_hash}"
   end
 end

test/mailers/reviewer_mailer_test.rb

@@ -6,6 +6,7 @@ class ReviewerMailerTest < ActionMailer::TestCase
     candidate = candidates :dawn
     mail = ReviewerMailer.candidate_submission candidate
     assert_match "Results", mail.subject
+    assert_match candidate.test_hash, mail.subject
     assert_equal candidate.quiz.reviewers.map(&:email), mail.to
     assert_equal [ENV["default_mail_from"]], mail.from
     assert_match candidate.test_hash, mail.body.encoded