[rpc] fix test_debug_info for python 3.5 (#34828)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34828
python 3.5 does not ensure ordering of dictionary keys, this was added
in python 3.6+. Fixing this so the test is no longer flaky in 3.5. Tested by
500 stresstests with python 3.5
ghstack-source-id: 100426555
Test Plan: 500 stress tests in python 3.5
Differential Revision: D20474996
fbshipit-source-id: 89b614a32363d1e7f3f7a4f27bec4fd7d507721d
