ctest_configure: Propagate CTEST_USE_LAUNCHERS from caller to project

If `CTEST_USE_LAUNCHERS` is `TRUE` in a CTest script then the
`ctest_configure` command will add `-DCTEST_USE_LAUNCHERS:BOOL=TRUE` to
the cmake command used to configure the project.  This allows a project
to only set `CTEST_USE_LAUNCHERS` in a ctest script and have launchers
work.
Status Job ID Name Coverage
  External
passed kwrobot-branch-check