Currently "semi_persist_dir" is not configurable. This may become a problem in certain scenarios. For example, the default value of "semi_persist_dir" is "/tmp" (https://github.com/apache/beam/blob/master/sdks/python/container/boot.go#L48) in Python SDK harness. When the environment type is "PROCESS", the disk of "/tmp" may be filled up and unexpected issues will occur in production environment. We should provide a way to configure "semi_persist_dir" in EnvironmentFactory at the runner side.