Fix bug where URL does not show for functions

Affects functions deployed on Knative 0.5 clusters

app/serializers/projects/serverless/service_entity.rb

@@ -44,7 +44,7 @@ module Projects
       end
 
       expose :url do |service|
-        service.dig('status', 'url')
+        service.dig('status', 'url') || "http://#{service.dig('status', 'domain')}"
       end
 
       expose :description do |service|