Fix trending projects Spinach failure

The trending projects list is now pre-calculated. To make this work
with the Spinach test, we have to manually refresh the list.

Partial fix to #23378

features/explore/projects.feature

@@ -128,6 +128,7 @@ Feature: Explore Projects
     And project "Archive" has comments
     And I sign in as a user
     And project "Community" has comments
+    And trending projects are refreshed
     When I visit the explore trending projects
     Then I should see project "Community"
     And I should not see project "Internal"

features/steps/shared/project.rb

@@ -218,6 +218,10 @@ module SharedProject
     2.times { create(:note_on_issue, project: project) }
   end
 
+  step 'trending projects are refreshed' do
+    TrendingProject.refresh!
+  end
+
   step 'project "Shop" has labels: "bug", "feature", "enhancement"' do
     project = Project.find_by(name: "Shop")
     create(:label, project: project, title: 'bug')