ci Avoid CI failure before a test has been retry 3 times

MR !111 (merged) modify the CI, to run ctest multiple times. Once for test that can work in parallel mode, and twice to rerun the failing test in sequential mode. But the CI was catching the first ctest return code. This first code was an error as some test aren't intended to run in parallel. This commit change the ci to use the ctest command only once.

@lea.vauchier PTAL