Improve fragment caching rules at projects dashboard

app/views/shared/projects/_project.html.haml

@@ -7,7 +7,7 @@
 - show_last_commit_as_description = false unless local_assigns[:show_last_commit_as_description] == true && project.commit
 - css_class += " no-description" if project.description.blank? && !show_last_commit_as_description
 - cache_key = [project.namespace, project, controller.controller_name, controller.action_name, current_application_settings, 'v2.3']
-- cache_key.push(project.commit.status) if project.commit.try(:status)
+- cache_key.push(project.commit&.sha, project.commit&.status)
 
 %li.project-row{ class: css_class }
   = cache(cache_key) do