tests: Fix typo in test comment

Change-Id: Ibcb07fe5f357e001e9d91897eebd1dfce78198d6
diff --git a/tests/layer_validation_tests.cpp b/tests/layer_validation_tests.cpp
index d03e6b4..1ca760c 100644
--- a/tests/layer_validation_tests.cpp
+++ b/tests/layer_validation_tests.cpp
@@ -1708,7 +1708,7 @@
     VkShaderObj fs(&test_device, bindStateFragShaderText,
         VK_SHADER_STAGE_FRAGMENT_BIT, this);
 
-    // Set polygonMode to unsupporte value POINT, should fail
+    // Set polygonMode to unsupported value POINT, should fail
     m_errorMonitor->SetDesiredFailureMsg(
         VK_DEBUG_REPORT_ERROR_BIT_EXT,
         "polygonMode cannot be VK_POLYGON_MODE_POINT or VK_POLYGON_MODE_LINE");