[clang] [git-clang-format] Don't format the line preceding a deletion (PR #215946)

[Aiden Grossman via cfe-commits]

https://github.com/boomanaiden154 approved this pull request.

LGTM.

I put an item on my TODO list a year or two ago to add in some testing for this script, but never got around to actually doing anything. It's unfortunate that we can't add regression tests here, but that's certainly outside the scope of this PR.

https://github.com/llvm/llvm-project/pull/215946