Fix k8s deployment marshal error with EMS workers

The `.ems_id_from_queue_name` method returns an integer and all env var
values have to be strings.

app/models/miq_worker/deployment_per_worker.rb

@@ -5,7 +5,7 @@ module DeploymentPerWorker
     def create_container_objects
       ContainerOrchestrator.new.create_deployment(worker_deployment_name) do |definition|
         configure_worker_deployment(definition, 1)
-        definition[:spec][:template][:spec][:containers].first[:env] << {:name => "EMS_ID", :value => self.class.ems_id_from_queue_name(queue_name)}
+        definition[:spec][:template][:spec][:containers].first[:env] << {:name => "EMS_ID", :value => self.class.ems_id_from_queue_name(queue_name).to_s}
       end
     end