Use new gitlab-shell v2.3.0

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

GITLAB_SHELL_VERSION

-2.2.0
+2.3.0

config/application.rb

@@ -92,5 +92,8 @@ module Gitlab
 
     redis_config_hash[:namespace] = 'cache:gitlab'
     config.cache_store = :redis_store, redis_config_hash
+
+    # This is needed for gitlab-shell
+    ENV['GITLAB_PATH_OUTSIDE_HOOK'] = ENV['PATH']
   end
 end