[Windows] Remove LLVM standalone installation

[kasper93]

LLVM is already included in the Visual Studio installation. This duplication creates conflicts between versions. The current MSVC C++ standard library requires at least Clang 17, while the standalone LLVM is 16.

There is no reason to include two different LLVM versions. Use the one from the Visual Studio installation. Should anyone need standalone LLVM, they can install it with a single command: choco install llvm.

Fixes: #10001

Check list

• [x] Related issue / work item is attached
• [x] Tests are written (if applicable)
• [x] Documentation is updated (if applicable)
• [ ] Changes are tested and related VM images are successfully generated