Stop modifying the global logger on `import functorch` (#86147)
Fixes https://github.com/pytorch/pytorch/issues/85952
`logging.basicConfig` modifies the global logger which affects other
programs. importing a package should generally be side-effect free so
this PR gets rid of that call.
Test Plan:
- tested locally
Pull Request resolved: https://github.com/pytorch/pytorch/pull/86147
Approved by: https://github.com/ezyang
