Adding test in skip list since core dump is now disabled.

Change-Id: Ibd5688f94896192d1d0f200f883888c721e99f34
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/test_lists/skip_test_witherspoon b/test_lists/skip_test_witherspoon
index 5dd743d..9333f8f 100644
--- a/test_lists/skip_test_witherspoon
+++ b/test_lists/skip_test_witherspoon
@@ -26,3 +26,5 @@
 -e Check_BMC_Memory_Device_Type_Property_Is_Set
 # MRW changes required for this to work.
 -e Test_GPU_SDR_Info_At_Power_On
+# Core dump is disabled.
+-e Verify_Core_Dump_Size