virtual9 test was fixed in eca9b59

tautschnig · jezhiggins · commit 8866f458b96f · 2021-02-03T14:54:48.000Z
Mark it as CORE instead of KNOWNBUG.
diff --git a/jbmc/regression/jbmc/virtual9/test.desc b/jbmc/regression/jbmc/virtual9/test.desc
@@ -1,4 +1,4 @@
-KNOWNBUG
+CORE
 Test
 --program-only
 ^EXIT=0$
