message: CI: add a check which throws an error when we find `0` tests.
diff: @@ -81,6 +81,8 @@ stages:
  before_script: *default_before_script
  script:
  - cd ${CI_JOB_NAME/test/build}
  + - |
  + (( $(ctest -N | tail -1 | sed 's/Total Tests: //') != 0 )) || exit 1
  - ctest -V
  except:
  - schedules
  