[clang-tools-extra] [clang-tidy] Filter out googletest TUs in bugprone-unchecked-optional-access (PR #115051)

[Yitzhak Mandelbaum via cfe-commits]

ymand wrote:

> I am still confused why your team did not just disable this rule for test folder? It is normal cases that source code and test code have different quality metrics.

Our codebase doesn't use test folders. We have no foolproof way of distinguishing code from test based on the file system.

https://github.com/llvm/llvm-project/pull/115051