Fix pages_url for mixed case paths

Related to https://gitlab.com/gitlab-org/gitlab/-/issues/224470.

app/models/project.rb

@@ -1699,7 +1699,7 @@ class Project < ApplicationRecord
 
   def pages_url
     url = pages_group_url
-    url_path = full_path.partition('/').last
+    url_path = full_path.partition('/').last.downcase
 
     # If the project path is the same as host, we serve it as group page
     return url if url == "#{Settings.pages.protocol}://#{url_path}"

changelogs/unreleased/224470-mixed-case-pages-url.yml

+---
+title: Fix pages_url for projects with mixed case path
+merge_request: 35300
+author:
+type: fixed

spec/models/project_spec.rb

@@ -1651,6 +1651,14 @@ RSpec.describe Project do
       let(:project_name) { 'group.example.com' }
 
       it { is_expected.to eq("http://group.example.com") }
+
+      context 'mixed case path' do
+        before do
+          project.update!(path: 'Group.example.com')
+        end
+
+        it { is_expected.to eq("http://group.example.com") }
+      end
     end
 
     context 'project page' do