add staircase page to the shared ownership scheme subsection fix file name

app/models/form/sales/subsections/shared_ownership_scheme.rb

@@ -8,7 +8,9 @@ class Form::Sales::Subsections::SharedOwnershipScheme < ::Form::Subsection
   end
 
   def pages
-    @pages ||= []
+    @pages ||= [
+      Form::Sales::Pages::Staircase.new(nil, nil, self),
+    ]
   end
 
   def displayed_in_tasklist?(log)

spec/models/form/sales/subsections/shared_ownership_scheme_spec.rb

@@ -13,7 +13,9 @@ RSpec.describe Form::Sales::Subsections::SharedOwnershipScheme, type: :model do
 
   it "has correct pages" do
     expect(shared_ownership_scheme.pages.map(&:id)).to eq(
-      %w[],
+      %w[
+        staircasing
+      ],
     )
   end
 

spec/models/form_handler_spec.rb

@@ -52,14 +52,14 @@ RSpec.describe FormHandler do
     it "is able to load a current sales form" do
       form = form_handler.get_form("current_sales")
       expect(form).to be_a(Form)
-      expect(form.pages.count).to eq(68)
+      expect(form.pages.count).to eq(69)
       expect(form.name).to eq("2022_2023_sales")
     end
 
     it "is able to load a previous sales form" do
       form = form_handler.get_form("previous_sales")
       expect(form).to be_a(Form)
-      expect(form.pages.count).to eq(68)
+      expect(form.pages.count).to eq(69)
       expect(form.name).to eq("2021_2022_sales")
     end
   end