[clang-tools-extra] [clang-tidy] Add a release note about unchecked-optional-access smart pointer caching (PR #122290)

[Jan Voung via cfe-commits]

jvoung wrote:

> program:run-clang-tidy

Sure thing --

Done separately in https://github.com/llvm/llvm-project/pull/122475 (I kept the "Improved" cluster together, vs moving `run-clang-tidy` to be after the "Removed" block including the table)

For `readability-identifier-naming` it looks like @HerrCai0907 already reordered that in https://github.com/llvm/llvm-project/commit/c01ffab6e1dac13a344a06677f413e55073d0580


https://github.com/llvm/llvm-project/pull/122290