tests: Fix crash in Windows Release builds

Change-Id: I65258cc7a0e9682717e16facd1d3f168cb444427
diff --git a/tests/layer_validation_tests.cpp b/tests/layer_validation_tests.cpp
index 0afd752..ff95397 100644
--- a/tests/layer_validation_tests.cpp
+++ b/tests/layer_validation_tests.cpp
@@ -3098,6 +3098,7 @@
     vkQueueSubmit(m_device->m_queue, 1, &submit_info, VK_NULL_HANDLE);
     m_errorMonitor->VerifyNotFound();
 
+    vkQueueWaitIdle(m_device->m_queue);
     vkDestroyFence(m_device->device(), fence, nullptr);
     vkDestroyRenderPass(m_device->device(), rp, nullptr);
     vkDestroyFramebuffer(m_device->device(), fb, nullptr);