[clang-tools-extra] [clang-tidy] Check for `-ignore-insert-conflict` support before using it in `apply_fixes` in `run-clang-tidy.py` (PR #127066)

[Vicente Mataix Ferrándiz via cfe-commits]

https://github.com/loumalouomega edited https://github.com/llvm/llvm-project/pull/127066