TestGpuNnapi: add missing sType for VkExternalBufferProperties am: ff83e506bf am: ccb58e838d

Original change: https://android-review.googlesource.com/c/platform/packages/modules/NeuralNetworks/+/2308100

Change-Id: Ic0326e781e4e32f4d76f2b8321d49dc853f81517
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>