Remove trailing references to GPO in IdV

app/services/idv/gpo_mail.rb

@@ -17,7 +17,7 @@ def profile_too_old?
       current_user.pending_profile.created_at < min_creation_date
     end
 
-    # Next two methods are analytics helpers used from GpoController and ReviewController
+    # Next two methods are analytics helpers used from RequestLetterController and ReviewController
 
     # Caveat: If the user succeeds on their final phone attempt, the :proof_address
     # RateLimiter is reset to 0. But they probably wouldn't be doing verify by mail

spec/features/idv/steps/gpo_otp_verification_step_spec.rb → spec/features/idv/steps/enter_code_step_spec.rb

@@ -1,6 +1,6 @@
 require 'rails_helper'
 
-RSpec.feature 'idv gpo otp verification step' do
+RSpec.feature 'idv enter letter code step' do
   include IdvStepHelper
 
   let(:otp) { 'ABC123' }

spec/features/idv/steps/gpo_step_spec.rb → spec/features/idv/steps/request_letter_step_spec.rb

@@ -1,6 +1,6 @@
 require 'rails_helper'
 
-RSpec.feature 'idv gpo step' do
+RSpec.feature 'idv request letter step' do
   include IdvStepHelper
   include OidcAuthHelper