Add missing attribute to budget strong params

app/controllers/admin/budgets_wizard/budgets_controller.rb

@@ -37,8 +37,8 @@ class Admin::BudgetsWizard::BudgetsController < Admin::BudgetsWizard::BaseContro
     end
 
     def allowed_params
-      valid_attributes = [:currency_symbol, :voting_style, administrator_ids: [], valuator_ids: [],
-                          image_attributes: image_attributes]
+      valid_attributes = [:currency_symbol, :voting_style, :main_link_url, administrator_ids: [],
+                          valuator_ids: [], image_attributes: image_attributes]
 
       valid_attributes + [translation_params(Budget)]
     end

spec/system/admin/budgets_wizard/budgets_spec.rb

@@ -7,6 +7,9 @@ describe "Budgets wizard, first step", :admin do
       click_button "Create new budget"
       click_link "Create multiple headings budget"
 
+      fill_in "Name", with: "M30 - Summer campaign"
+      fill_in "Text on the link", with: "Participate now!"
+      fill_in "The link takes you to (add a link)", with: "https://consulproject.org"
       fill_in "Name", with: "M30 - Summer campaign"
       click_button "Continue to groups"