acl-plugin: make test: shuffle applied ACLs as part of the tests

During the testing of 94f9a6de3f
I realized there was no test coverage for the cases where
the ACLs are added then modified while having beein applied.

This change adds some simple shuffling to l2l3 ACL test set,
whereby after each of the ACLs being applied, a few extra ACLs
are applied at the front and the back of the list, and are changed
several times, the base for the changes being the set of all the
ACEs that are being applied previously.

After these few shuffles, the routine restores the applied ACLs
and proceeds to the test as usual.

Change-Id: Ieda2aa5b7963746d62484e54719309de9c1ee752
Signed-off-by: Andrew Yourtchenko <ayourtch@gmail.com>

test/vpp_papi_provider.py

@@ -2765,6 +2765,12 @@ class VppPapiProvider(object):
                         {'acl_index': acl_index},
                         expected_retval=expected_retval)
 
+    def acl_interface_list_dump(self, sw_if_index=0xFFFFFFFF,
+                                expected_retval=0):
+        return self.api(self.papi.acl_interface_list_dump,
+                        {'sw_if_index': sw_if_index},
+                        expected_retval=expected_retval)
+
     def macip_acl_add(self, rules, tag=""):
         """ Add MACIP acl