fix opencv_run_all_tests_unix.sh script:
fix opencv_run_all_tests_unix.sh script:

use `bash` shell instead of `sh`, since on Ubuntu `sh` by default is `dash`,
and `dash` doesn't support `PIPESTATUS` feature used in this sctipt
opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv