Fix merge typo

Author: AndriiMysko

lib/travis/api/v3/models/v2_plan_config.rb

@@ -1,7 +1,7 @@
 module Travis::API::V3
   class Models::V2PlanConfig
     attr_reader :id, :name, :private_repos, :starting_price, :starting_users, :plan_type,
-                :private_credits, :public_credits, :addon_configs, :concurrency_limit, :available_standalone_addons, :auto_refill_enabled, :trial_plan
+                :private_credits, :public_credits, :addon_configs, :concurrency_limit, :available_standalone_addons, :auto_refill_enabled, :trial_plan,
                 :annual, :auto_refill_thresholds, :auto_refill_amounts
 
     def initialize(attrs)