idf-ci discovers pyproject.toml pytest config and runs a separate
collection pass with --target all, which finds 0 target tests and
raises RuntimeError. Add to .idf_ci.toml exclude_dirs instead of
deleting tests. Restore all 227 unit tests with lint/mypy fixes.
(cherry picked from commit 205bc49fd6)
Co-authored-by: Zhou Xiao <zhouxiao@espressif.com>
