It's not possible to override CMAKE_CONFIGURATION_TYPES when configuring a qt repo against a -debug-and-release Qt

We hard-code a set(CMAKE_CONFIGURATION_TYPES CACHE FORCE) in lib/cmake/Qt6BuildInternals/QtBuildInternalsExtra.cmake when configuring a -debug-and-release qtbase.

Afterwards calling

qt-configure-module.bat .. -- -DCMAKE_CONFIGURATION_TYPES=Release

doesn't affect anything.

This is different to how we treat single-config configuration, where an override is possible by passing -DCMAKE_BUILD_TYPE.

We should consider fixing this, but care must be taken because touching code there is always prone due regressions due to multiple use cases (per-repo configures, top-level configure, standalone tests, standalone sql drivers project, user projects, mixing multi-config qt with single config qt repo or project etc).