Fix typo in Oracle support

[latortuga]

No description provided.

[latortuga]

I'm confident in this change because I put the following patch at the end of my Rpush initializer and everything is working with Oracle:

if Rpush::VERSION == '2.5.0'
  require 'rpush'
  require 'rpush/daemon'
  require 'rpush/daemon/store/active_record'

  module Rpush
    module Daemon
      module Store
        class ActiveRecord
          private

          def claim(relation)
            notifications = relation.lock(true).to_a
            @using_oracle ? notifications.sort_by(&:created_at) : notifications
          end
        end
      end
    end
  end
end

[ileitch]

😱 oops!