Remove signup_onboarding feature flag

This enables the onboarding flow for gitlab.com to guide users to create
a group and project during sign up and onboard them with the learn
gitlab project.

changelogs/unreleased/nicolasdular-cleanup-signup-onboarding-ff.yml

+---
+title: Let users create groups and projects at signup and onboard them through issues on gitlab.com
+merge_request: 58301
+author:
+type: added

ee/app/helpers/ee/welcome_helper.rb

@@ -69,7 +69,7 @@ module EE
     end
 
     def signup_onboarding_enabled?
-      ::Gitlab.dev_env_or_com? && ::Feature.enabled?(:signup_onboarding, default_enabled: true)
+      ::Gitlab.dev_env_or_com?
     end
   end
 end

ee/config/feature_flags/development/signup_onboarding.yml

----
-name: signup_onboarding
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/52905
-rollout_issue_url: 
-milestone: '13.9'
-type: development
-group: group::conversion
-default_enabled: true

ee/spec/features/registrations/welcome_spec.rb

@@ -5,19 +5,17 @@ require 'spec_helper'
 RSpec.describe 'Welcome screen', :js do
   let_it_be(:user) { create(:user) }
 
-  let(:signup_onboarding_enabled) { true }
-  let(:user_has_memberships) { false }
-  let(:in_subscription_flow) { false }
-  let(:in_trial_flow) { false }
+  context 'when on GitLab.com' do
+    let(:user_has_memberships) { false }
+    let(:in_subscription_flow) { false }
+    let(:in_trial_flow) { false }
 
-  describe 'on GitLab.com' do
     before do
       allow(Gitlab).to receive(:com?).and_return(true)
       gitlab_sign_in(user)
       allow_any_instance_of(EE::WelcomeHelper).to receive(:user_has_memberships?).and_return(user_has_memberships)
       allow_any_instance_of(EE::WelcomeHelper).to receive(:in_subscription_flow?).and_return(in_subscription_flow)
       allow_any_instance_of(EE::WelcomeHelper).to receive(:in_trial_flow?).and_return(in_trial_flow)
-      stub_feature_flags(signup_onboarding: signup_onboarding_enabled)
 
       visit users_sign_up_welcome_path
     end
@@ -51,14 +49,19 @@ RSpec.describe 'Welcome screen', :js do
         expect(page).not_to have_content('Your profile')
       end
     end
+  end
 
-    context 'when onboarding_signup is disabled' do
-      let(:signup_onboarding_enabled) { false }
+  context 'when not on GitLab.com' do
+    before do
+      allow(Gitlab).to receive(:com?).and_return(false)
+      gitlab_sign_in(user)
 
-      it 'does not show the progress bar' do
-        expect(page).not_to have_content('Your profile')
-        expect(page).to have_content('Get started!')
-      end
+      visit users_sign_up_welcome_path
+    end
+
+    it 'does not show the progress bar' do
+      expect(page).not_to have_content('Your profile')
+      expect(page).to have_content('Get started!')
     end
   end
 end

ee/spec/helpers/ee/welcome_helper_spec.rb

@@ -267,17 +267,14 @@ RSpec.describe EE::WelcomeHelper do
   describe '#signup_onboarding_enabled?' do
     subject { helper.signup_onboarding_enabled? }
 
-    where(:is_com, :feature_flag_enabled, :result) do
-      true  | true  | true
-      true  | false | false
-      false | true  | false
-      false | false | false
+    where(:is_com, :result) do
+      true  | true
+      false | false
     end
 
     with_them do
       before do
         expect(Gitlab).to receive(:com?).and_return(is_com)
-        stub_feature_flags(signup_onboarding: feature_flag_enabled)
       end
 
       it { is_expected.to eq(result) }