[clang] [clang][docs] Add all clang-tools-extra to 'ClangTools.rst' (PR #148622)

[Carlos Galvez via cfe-commits]

carlosgalvezp wrote:

Maybe this has been already discussed, but it feels strange to me to capitalize the names of the tools, like Clang-Tidy. Why is that? I don't know what is "correct" in this case, do we have such a pattern in other documents?

https://github.com/llvm/llvm-project/pull/148622