Make tests independent of Setting["org_name"]

So tests won't fail when an institution changes the default organization
name.

The tests are also easier to understand now, since it's more obvious
where the "CONSUL" text is coming from.

spec/lib/email_digests_spec.rb

@@ -56,6 +56,7 @@ describe EmailDigest do
     let(:user) { create(:user) }
 
     it "delivers email if notifications pending" do
+      Setting["org_name"] = "CONSUL"
       create(:notification, :for_proposal_notification, user: user)
 
       reset_mailer