add user scaffold

spec/routing/users_routing_spec.rb

@@ -0,0 +1,9 @@
+require "rails_helper"
+
+RSpec.describe UsersController, type: :routing do
+  describe "routing" do
+    it "routes to #show" do
+      expect(get: "/users/1").to route_to("users#show", id: "1")
+    end
+  end
+end