Fix the namespace mismatch problem when deploying with a single YAML file (#1344)

If a user deploys fission in the namespace which is different from the one in the single YAML file generated by helm, fission components won't be able to talk to each other due to the wrong namespace appends after the service address.

This PR adds --namespace when generating the YAML file to prevent the mismatch problem.

pkg/executor/executor_test.go

@@ -175,7 +175,7 @@ func TestExecutor(t *testing.T) {
 
 	// create poolmgr
 	port := 9999
-	err = StartExecutor(logger, fissionNs, functionNs, "fission-builder", port)
+	err = StartExecutor(logger, functionNs, "fission-builder", port)
 	if err != nil {
 		log.Panicf("failed to start poolmgr: %v", err)
 	}