Merge topic 'ctest-add_subdirectory'

7c5a120c38 Tests: Add case covering both ctest subdirectory commands
04deda1d2a CTest: Extract common implementation of add_subdirectory and subdirs

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: buildbot <buildbot@kitware.com>
Merge-request: !6795