Vulkan: Remove invalid ASSERT in DescriptorSetDesc. This invalid ASSERT somehow was undetected pre-commit when landing the descriptor set cache CLs. It was code from before a refactor that broke the ASSERT's invariant condition. Bug: angleproject:7354 Change-Id: I4e84c78911e4c6aad826b1acabcd87216884509c Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3666250 Commit-Queue: Jamie Madill <jmadill@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Auto-Submit: Jamie Madill <jmadill@chromium.org> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>