[clang-tools-extra] [clang-tidy] support parameters file in command line (PR #120547)

[Julian Schmidt via cfe-commits]

https://github.com/5chmidti commented:

As this is not using `llvm::cl`, it is not automatically documented in `--help`. Maybe some sort of comment inside `ClangTidyHelp` would help with the discoverability from the CLI.

https://github.com/llvm/llvm-project/pull/120547