Fix regression in CMake configuration on Windows
Fix regression in CMake configuration on Windows

Warnings-as-errors were disabled in Debug builds.

Regression introduced in 5a4f6719529a10d26620351dd6d667b9873293bf: Enable warnings-as-errors in Debug and Release only

appleseedhq/appleseed,pjessesco/appleseed,appleseedhq/appleseed,appleseedhq/appleseed,Vertexwahn/appleseed,pjessesco/appleseed,Vertexwahn/appleseed,dictoon/appleseed,est77/appleseed,appleseedhq/appleseed,appleseedhq/appleseed,luisbarrancos/appleseed,dictoon/appleseed,luisbarrancos/appleseed,pjessesco/appleseed,luisbarrancos/appleseed,est77/appleseed,Vertexwahn/appleseed,luisbarrancos/appleseed,pjessesco/appleseed,dictoon/appleseed,luisbarrancos/appleseed,est77/appleseed,dictoon/appleseed,Vertexwahn/appleseed,pjessesco/appleseed,est77/appleseed,Vertexwahn/appleseed,dictoon/appleseed,est77/appleseed