[clang-tools-extra] [clang-tidy][NFC] swap cppcoreguidelines-narrowing-conversions and bugprone-narrowing-conversions (PR #120245)

[Carlos Galvez via cfe-commits]

carlosgalvezp wrote:

This change is not just a refactor, it leads to user-facing documentation changes (which check alias which), so I think it should be mentioned in the Release Notes. It doesn't cost anything to add it :) 

https://github.com/llvm/llvm-project/pull/120245