FIX: Prevent critical emails bypassing disable, and improve email test logic

- The test_email job is removed, because it was always being run synchronously (not in sidekiq)
- 34b29f62 added a bypass for critical emails, to match the spec. This removes the bypass, and removes the spec.
- This adapts the specs for 72ffabf6, so that they check for emails being sent
- This reimplements c2797921, allowing test emails to be sent even when emails are disabled

spec/components/email/sender_spec.rb

@@ -12,15 +12,24 @@ describe Email::Sender do
       before { SiteSetting.disable_emails = "yes" }
 
       it "doesn't deliver mail when mails are disabled" do
-        Mail::Message.any_instance.expects(:deliver_now).never
-        message = Mail::Message.new(to: moderator.email , body: "hello")
-        expect(Email::Sender.new(message, :hello).send).to eq(nil)
+        message = UserNotifications.email_login(moderator)
+        Email::Sender.new(message, :email_login).send
+
+        expect(ActionMailer::Base.deliveries).to eq([])
       end
 
       it "delivers mail when mails are disabled but the email_type is admin_login" do
-        Mail::Message.any_instance.expects(:deliver_now).once
-        message = Mail::Message.new(to: moderator.email , body: "hello")
+        message = UserNotifications.admin_login(moderator)
         Email::Sender.new(message, :admin_login).send
+
+        expect(ActionMailer::Base.deliveries.first.to).to eq([moderator.email])
+      end
+
+      it "delivers mail when mails are disabled but the email_type is test_message" do
+        message = TestMailer.send_test(moderator.email)
+        Email::Sender.new(message, :test_message).send
+
+        expect(ActionMailer::Base.deliveries.first.to).to eq([moderator.email])
       end
     end