[clang] [llvm] [clang-format] Add CI check confirming ClangFormatStyleOptions.rst is up-to-date. (PR #111513)

[Owen Pan via cfe-commits]

https://github.com/owenca commented:

@ichaer I suggest that you split the workflow part to another patch so that we can get the cmake part approved.

https://github.com/llvm/llvm-project/pull/111513