Error in clang-tidy 21
## Steps to reproduce
Updated clang-tidy in CI to LLVM 21.1.3.
## Expected behavior
clang-tidy should work correctly.
## Current behavior
The following error occurred, but this repository has no `__has_feature`.
```
Check of /builds/MusicScience37Projects/numerical-analysis/numerical-collection-cpp/test/units/regularization/unity_source.cpp finished with exit code 1.
error: missing '(' after '__has_feature' [clang-diagnostic-error]
```
## Note
issue