tests: Shorten local variable scope

Change-Id: I463c083bfa13879bca04090ca8f1a4696def5eb0
diff --git a/tests/layer_validation_tests.cpp b/tests/layer_validation_tests.cpp
index 8398d5c..eab5524 100644
--- a/tests/layer_validation_tests.cpp
+++ b/tests/layer_validation_tests.cpp
@@ -11512,8 +11512,6 @@
     ASSERT_NO_FATAL_FAILURE(InitState());
     ASSERT_NO_FATAL_FAILURE(InitRenderTarget());
 
-    const char *cannot_destroy_fence_message = "Fence 0x";
-
     m_commandBuffer->BeginCommandBuffer();
 
     VkEvent event;
@@ -11640,7 +11638,7 @@
     vkDestroySemaphore(m_device->device(), semaphore, nullptr);
     m_errorMonitor->VerifyFound();
 
-    m_errorMonitor->SetDesiredFailureMsg(VK_DEBUG_REPORT_ERROR_BIT_EXT, cannot_destroy_fence_message);
+    m_errorMonitor->SetDesiredFailureMsg(VK_DEBUG_REPORT_ERROR_BIT_EXT, "Fence 0x");
     vkDestroyFence(m_device->device(), fence, nullptr);
     m_errorMonitor->VerifyFound();