remove extra get_worker_id call in distributed rpc init (#26381)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/26381
Was looking through this definition and saw that it has 2 identical
definitions of get_worker_id. Tested by ensuring that all tests in
`test/test_rpc.py` still pass.
ghstack-source-id: 90347452
Test Plan: See above
Differential Revision: D17439495
fbshipit-source-id: 9a78340f7aefa5797e0ae837fbcfe24ebe3a775d
