Opsworks only runs in east-1

It doesn't have endpoints in every region, needs to be called in east-1,
so we may as well specify that to avoid it potentially being set by ENV

lib/oops/opsworks_deploy.rb

@@ -3,7 +3,7 @@ class OpsworksDeploy
     attr_accessor :stack_name, :app_name
 
     def initialize(app_name, stack_name)
-      @client = Aws::OpsWorks::Client.new
+      @client = Aws::OpsWorks::Client.new region: 'us-east-1'
       self.stack_name = stack_name
       self.app_name = app_name
     end