[clang] [clang-format] Add --strip-trailing-cr to diff in docs_updated.test (PR #119666)

[Aiden Grossman via cfe-commits]

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

Is the cleanup just running `black`? Would be better committed separately in my opinion. Either way, LGTM for both the cleanup and the test change.

https://github.com/llvm/llvm-project/pull/119666