adhere to rubocop guidelines

spec/factories.rb

@@ -1,10 +1,11 @@
+# frozen_string_literal: true
+
 FactoryBot.define do
-  
   factory :user do
     password = Faker::Internet.password(8)
 
     provider { %w(greenlight google twitter).sample }
-    uid { rand(10 ** 8) }
+    uid { rand(10**8) }
     name { Faker::Name.first_name }
     username { Faker::Internet.user_name }
     email { Faker::Internet.email }