get_init_configs issue in sandbox

[HYLcool]

After removing two lines of code in PR #597, there is an issue for Sandbox that could not find work_dir in later steps.

It's hard to resolve this issue by only changing the position of calling get_init_configs. Maybe we need to remove usages of Path from config namespaces, or rethink the implementation of StatsKeys.get_access_log.