Staging tests don't work with multiconfig generators

Created by: chuckatkins

The staging tests are expecting executables to be in bin/Foo whic is not the case for multi-config generators like Visual Studio and XCode. See https://open.cdash.org/testDetails.php?test=816980556&build=6179972

The test commands likely need to be adapted to use generator expressions like $<TARGET_FILE:Foo> instead of assuming ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/Foo