Properly format db.h and db.cc (#43027)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/43027
Format db.h and db.cc using the default formatter.
This change was split off of D22705434.
Test Plan: Wait for sandcastle.
Reviewed By: rohithmenon, marksantaniello
Differential Revision: D23113765
fbshipit-source-id: 3f02d55bfb055bda0fcba5122336fa001562d42e
