Merge topic 'ctest_cli_define_script_vars'

2e214f0a5b ctest: allow CTest Script variables to be set via the command-line
21b9c20592 ctest: extend config mapping to include script-only variables
68489471a6 ctest: refactor SetCMakeVariables to use a mapping table

Acked-by: Kitware Robot <kwrobot@kitware.com>
Tested-by: buildbot <buildbot@kitware.com>
Merge-request: !12060