[clang-tools-extra] [clang-tidy] `modernize-use-trailing-return-type`: add an option to apply to `void`-returning functions as well (PR #129406)

[Baranov Victor via cfe-commits]

vbvictor wrote:

@khuldraeseth, gentle ping, do you still wish to work on this check? 21th LLVM release will be soon, If you wish to have your changes in the upcoming release please rebase on main and fix suggested issues

https://github.com/llvm/llvm-project/pull/129406