Bug 238072, disable bad test temporarily

layout/reftests/generated-content/reftest.list

@@ -5,4 +5,4 @@
 == images-01.html images-01-ref.html
 == positioned-01.html positioned-01-ref.html
 == table-ignoring-whitespace-01.html table-ignoring-whitespace-01-ref.html
-== table-parts-01.html table-parts-01-ref.html
+fails == table-parts-01.html table-parts-01-ref.html  #  commented out temporarily