Remove fog aliyun hack

Seems to be no longer needed with fog-core >= 2.3.0

References:
- fog/fog-core#269
- fog/fog-aliyun#155

Author: johha

lib/cloud_controller/blobstore/fog/providers.rb

@@ -7,9 +7,6 @@
 Fog::Logger[:deprecation] = nil
 
 require 'fog/aliyun'
-# Hack until https://github.com/fog/fog-aliyun/pull/155 is merged and released
-Fog::Aliyun::Compute = Fog::Compute::Aliyun
-
 require 'fog/aws'
 require 'fog/local'
 require 'fog/google'