[clang-tools-extra] [Clang-Tidy] Fixed `cppcoreguidelines-init-variables` to handle ObjC for-in loops. (PR #191306)

[Dmitrii Kuragin via cfe-commits]

sstepashka wrote:

Just for the context: In our project (due to legacy reasons) much of the code is compiled as Objective-C++ because it includes Cocoa headers. Even if most of the code is strictly speaking C++ and some of the headers are shared with C++ and Objective-C[++] we would extremely value the check to be enabled for `.mm` and `-x objective-c++` cases.

It wasn't the best idea to include Cocoa headers in C++, but it is what it is now. 

https://github.com/llvm/llvm-project/pull/191306