Current user should be nil to prevent ActiveJob::DeserializationError errors in tests.

git-svn-id: http://svn.redmine.org/redmine/trunk@17671 e93f8b46-1217-0410-a6f0-8f06a7374b81

test/unit/project_copy_test.rb

@@ -39,6 +39,7 @@ class ProjectCopyTest < ActiveSupport::TestCase
            :documents
 
   def setup
+    User.current = nil
     ProjectCustomField.destroy_all
     @source_project = Project.find(2)
     @project = Project.new(:name => 'Copy Test', :identifier => 'copy-test')