fix typo (#1533)

spec/features/admin_users_spec.rb

@@ -94,7 +94,7 @@ describe Admin::UsersController do
         expect(users(:bob)).not_to be_active
       end
 
-      it "deactivates an existing user" do
+      it "activates an existing user" do
         users(:bob).deactivate!
         visit admin_users_path
         find(:css, "a[href='/admin/users/#{users(:bob).id}/activate']").click