Revert "pktact: disable no-op test DirectBadPacketBase"

This reverts commit 5d0e13ca68329148b693536bbadd87b8261f391a.

The priority was inherited by the subclasses, which wasn't the intention.
diff --git a/tests/pktact.py b/tests/pktact.py
index 67aa9bb..2f9267b 100644
--- a/tests/pktact.py
+++ b/tests/pktact.py
@@ -2046,8 +2046,6 @@
     Verify the packet is received at the egress port only
     """
 
-    priority = -1 # no-op base class
-
     RESULT_MATCH = "MATCH"
     RESULT_NOMATCH = "NO MATCH"
     RESULT_ANY = "ANY MATCH"