Branch protection rules block the GITHUB_TOKEN from dismissing reviews
(HTTP 403), so every push added another undismissable REQUEST_CHANGES
review. PR #27004 accumulated 12 identical blocking reviews.
Switch to COMMENT-only reviews. Findings still show inline on the diff
but don't create blocking reviews that require manual maintainer
dismissal. The CI check status (pass/fail) gates merging, not the
review state.
Also enable CMAKE_TESTING=ON in the clang-tidy build so test files get
proper include paths in compile_commands.json. Without this,
clang-tidy-diff runs on test files from the PR diff but can't resolve
gtest headers, producing false positives.
Fixes#27004
Signed-off-by: Ramon Roche <mrpollo@gmail.com>