[torch] Set default log level for torch elastic (#63214)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/63214
The default log level in fb and oss is different: in oss we use WARNING and in fb we use INFO.
Test Plan: unittests, f291441502
Reviewed By: cbalioglu
Differential Revision: D30296298
fbshipit-source-id: 89067352be767255fbc66e790ec333582de64c6c
