add skip_if_no_ports fixture back to test_snmp_default_route, it was …

…removed by mistack- test shouldn't run on setup with no ports

tests/snmp/test_snmp_default_route.py

@@ -10,7 +10,8 @@
 
 
 @pytest.mark.bsl
-def test_snmp_default_route(duthosts, enum_rand_one_per_hwsku_frontend_hostname, localhost, creds_all_duts, tbinfo):
+def test_snmp_default_route(duthosts, enum_rand_one_per_hwsku_frontend_hostname, localhost, 
+                            creds_all_duts, tbinfo, skip_if_no_ports):
     """compare the snmp facts between observed states and target state"""
 
     duthost = duthosts[enum_rand_one_per_hwsku_frontend_hostname]