Now we need to include EmailHelpers for each test

spec/models/deploy_key_spec.rb

 require 'spec_helper'
 
 describe DeployKey, models: true do
+  include EmailHelpers
+
   describe "Associations" do
     it { is_expected.to have_many(:deploy_keys_projects) }
     it { is_expected.to have_many(:projects) }

spec/models/key_spec.rb

 require 'spec_helper'
 
 describe Key, models: true do
+  include EmailHelpers
+
   describe "Associations" do
     it { is_expected.to belong_to(:user) }
   end