pytorch

bc6852c1 - Change TCPStore world_size and is_master to be optional (#51809)

Change TCPStore world_size and is_master to be optional (#51809) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/51809 Changes to TCPStore which will make world_size and is_master optional parameters for initialization. API before change: ```python # arguments: host_name, port, world_size, is_master, timeout=300s server_store = dist.TCPStore("127.0.0.1", 0, 2, True) client_store = dist.TCPStore("127.0.0.1", 0, 2, False) ``` API after change: ```python # arguments: host_name, port, world_size=-1, is_master=False, timeout=300s server_store = dist.TCPStore("127.0.0.1", 0, is_master=True) client_store = dist.TCPStore("127.0.0.1", 0) ``` Test Plan: Imported from OSS Reviewed By: heitorschueroff Differential Revision: D26461770 Pulled By: H-Huang fbshipit-source-id: 5b2157029c73e8706e158cd49ecce60c9f3a7f41