Scripts: Ignore robin_hood headers in VVL Needed to unblock vulkan-deps roll. Example bad roll: https://chromium-review.googlesource.com/c/angle/angle/+/2784701 Fallout from upstream changes: https://github.com/KhronosGroup/Vulkan-ValidationLayers/issues/2639 TBR: jmadill@google.com Bug: angleproject:5791 Change-Id: Idf4a0f6b4a7ef04e48d84110cd9d30887ebff9cf Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2784712 Reviewed-by: Cody Northrop <cnorthrop@google.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Cody Northrop <cnorthrop@google.com>