Some tests want to test the config-less build type (at least `Tests/RunCMake/add_custom_command@WorkingDirectory`).
@@ -32,6 +32,7 @@ endif()
unset(ENV{NO_COLOR})
unset(ENV{CLICOLOR})
unset(ENV{CLICOLOR_FORCE})
+unset(ENV{CMAKE_BUILD_TYPE})
unset(ENV{CMAKE_GENERATOR})
unset(ENV{CMAKE_GENERATOR_INSTANCE})
unset(ENV{CMAKE_GENERATOR_PLATFORM})