🐛 Ensure that `app.include_router` merges nested lifespans (#9630)
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>
Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>
