[clang-tools-extra] Enforce SL.con.3: Add check to replace operator[] with at() (PR #90043)

[Paul Heidekrüger via cfe-commits]

PBHDK wrote:

> Yes, you can just submit new PR, reference this one.

Done! Here it is: https://github.com/llvm/llvm-project/pull/95220

https://github.com/llvm/llvm-project/pull/90043