Revert "Avoid CTest 2.6.4 dashboard script crash"

The --force-new-ctest-process option does not do anything in the context
where we added it, so we remove the useless change.

Tests/CMakeInstall.cmake

@@ -33,7 +33,6 @@ if(CMake_TEST_INSTALL)
   add_test(CMake.Install
     ${CMake_TEST_INSTALL_CTest}
     ${CMake_TEST_INSTALL_CONFIG}
-    --force-new-ctest-process
     --build-and-test ${CMAKE_SOURCE_DIR} ${CMAKE_BINARY_DIR}
     --build-generator ${CMAKE_GENERATOR} # Not CMAKE_TEST_GENERATOR
     --build-project CMake