Fix projects without repo and wiki

When repo and wiki are disabled for a project,
we're showing issues so we'll need to set @issuable_meta_data
otherwise it would be giving nil errors. See:

https://sentry.gitlap.com/gitlab/staginggitlabcom/issues/23106/

app/controllers/projects_controller.rb

@@ -267,8 +267,9 @@ class ProjectsController < Projects::ApplicationController
         @project_wiki = @project.wiki
         @wiki_home = @project_wiki.find_page('home', params[:version_id])
       elsif @project.feature_available?(:issues, current_user)
-        @issues = issues_collection
-        @issues = @issues.page(params[:page])
+        @issues = issues_collection.page(params[:page])
+        @collection_type = 'Issue'
+        @issuable_meta_data = issuable_meta_data(@issues, @collection_type)
       end
 
       render :show

spec/controllers/projects_controller_spec.rb

@@ -78,6 +78,7 @@ describe ProjectsController do
 
         it 'shows issues list page if wiki is disabled' do
           project.project_feature.update_attribute(:wiki_access_level, ProjectFeature::DISABLED)
+          create(:issue, project: project)
 
           get :show, namespace_id: project.namespace, id: project