Fixes undefined method error on osx_dmg_source_url.

Author: mitchellallison

libraries/provider_git_client_osx.rb

@@ -11,7 +11,7 @@ class Osx < Chef::Provider::GitClient
             app new_resource.osx_dmg_app_name
             package_id new_resource.osx_dmg_package_id
             volumes_dir new_resource.osx_dmg_volumes_dir
-            source new_resource.osx_dmg_source_url
+            source new_resource.osx_dmg_url
             checksum new_resource.osx_dmg_checksum
             type 'pkg'
             action :install