vhost_SUITE: Clean up default limit and policy changes in cases

These changes to the defaults can affect other test cases. In particular
it will affect the time to live and deletion events in the vhost
deletion idempotency case.

(cherry picked from commit f093831)

Author: the-mikedavis

deps/rabbit/test/vhost_SUITE.erl

@@ -506,9 +506,15 @@ vhost_is_created_with_default_limits(Config) ->
     Env = [{vhosts, [{<<"id">>, Limits++Pattern}]}],
     ?assertEqual(ok, rabbit_ct_broker_helpers:rpc(Config, 0,
                             application, set_env, [rabbit, default_limits, Env])),
-    ?assertEqual(ok, rabbit_ct_broker_helpers:add_vhost(Config, VHost)),
-    ?assertEqual(Limits, rabbit_ct_broker_helpers:rpc(Config, 0,
-                            rabbit_vhost_limit, list, [VHost])).
+    try
+        ?assertEqual(ok, rabbit_ct_broker_helpers:add_vhost(Config, VHost)),
+        ?assertEqual(Limits, rabbit_ct_broker_helpers:rpc(Config, 0,
+                                rabbit_vhost_limit, list, [VHost]))
+    after
+        rabbit_ct_broker_helpers:rpc(
+          Config, 0,
+          application, unset_env, [rabbit, default_limits])
+    end.
 
 vhost_is_created_with_operator_policies(Config) ->
     VHost = <<"vhost1">>,
@@ -517,9 +523,15 @@ vhost_is_created_with_operator_policies(Config) ->
     Env = [{operator, [{PolicyName, Definition}]}],
     ?assertEqual(ok, rabbit_ct_broker_helpers:rpc(Config, 0,
                             application, set_env, [rabbit, default_policies, Env])),
-    ?assertEqual(ok, rabbit_ct_broker_helpers:add_vhost(Config, VHost)),
-    ?assertNotEqual(not_found, rabbit_ct_broker_helpers:rpc(Config, 0,
-                            rabbit_policy, lookup_op, [VHost, PolicyName])).
+    try
+        ?assertEqual(ok, rabbit_ct_broker_helpers:add_vhost(Config, VHost)),
+        ?assertNotEqual(not_found, rabbit_ct_broker_helpers:rpc(Config, 0,
+                                rabbit_policy, lookup_op, [VHost, PolicyName]))
+    after
+        rabbit_ct_broker_helpers:rpc(
+          Config, 0,
+          application, unset_env, [rabbit, default_policies])
+    end.
 
 vhost_is_created_with_default_user(Config) ->
     VHost = <<"vhost1">>,