Restore config after vxlan_crm from vxlan_ecmp. (sonic-net#17767)

What is the motivation for this PR?
test_vxlan_crm.py was recently enabled for smartswitch, which uses the same setup fixture as test_vxlan_ecmp.py. However, the tests in test_vxlan_ecmp.py have additional cleanup code to handle these BFD entries which is missing in test_vxlan_crm.py.

How did you do it?
Added a config restore fixture, same as in sonic-net#17046, to test_vxlan_ecmp.py which is re-used by test_vxlan_crm.py

How did you verify/test it?
Ran test_cacl_application.py after running test_vxlan_crm.py and it's now passing with the fix in place. Also checked that iptable is cleaned up after running test_vxlan_crm.py.

Signed-off-by: Guy Shemesh <[email protected]>

Author: dypet

tests/vxlan/test_vxlan_ecmp.py

@@ -60,6 +60,8 @@
 
 from tests.common.helpers.assertions import pytest_assert
 from tests.common.fixtures.ptfhost_utils import copy_ptftests_directory     # noqa F401
+from tests.common.fixtures.duthost_utils import backup_and_restore_config_db_on_duts    # noqa F401
+from tests.common.config_reload import config_reload
 from tests.common.utilities import wait_until
 from tests.ptf_runner import ptf_runner
 from tests.common.vxlan_ecmp_utils import Ecmp_Utils
@@ -140,7 +142,8 @@ def fixture_setUp(duthosts,
                   rand_one_dut_hostname,
                   minigraph_facts,
                   tbinfo,
-                  encap_type):
+                  encap_type,
+                  backup_and_restore_config_db_on_duts):        # noqa F811
     '''
         Setup for the entire script.
         The basic steps in VxLAN configs are:
@@ -339,6 +342,14 @@ def fixture_setUp(duthosts,
     setup_crm_interval(data['duthost'], int(data['original_crm_interval']))
 
 
+@pytest.fixture(scope="module", autouse=True)
+def restore_config_by_config_reload(duthosts, rand_one_dut_hostname, localhost):
+    yield
+    duthost = duthosts[rand_one_dut_hostname]
+
+    config_reload(duthost, safe_reload=True)
+
+
 @pytest.fixture(scope="module")
 def default_routes(setUp, encap_type):
     vnet = list(setUp[encap_type]['vnet_vni_map'].keys())[0]