tests: Explicitly set is_dxgi_handle to true in test code since the d3d11 allocator gives us non-NT handles
Co-authored-by: Korcan Hussein <korcan.hussein@collabora.com>
Part-of: <https://gitlab.freedesktop.org/monado/monado/-/merge_requests/2579>
authored by Krzysztof Lesiak Korcan Hussein and committed by Marge Bot 314529d0 a5301c6f