add scalapack test to gitlab CI
The scalapack tests are built only when --enable-scalapack-tests option is used with configure. We should test it in gitlab CI as well, but MKL 11.3 is strangely failing on buildtest. The problem seems to disappear when switching to MKL 2017 (even though it works on Hydra for both 11.3 and 2017). So we should return this test when we switch to MKL 2017 on buildtest.