tests instantiating clients w/o shutting down (#16755)

noticed via their port still in use messages.

agent/consul/client_test.go

@@ -824,6 +824,7 @@ func TestClient_ReloadConfig(t *testing.T) {
 	deps := newDefaultDeps(t, &Config{NodeName: "node1", Datacenter: "dc1"})
 	c, err := NewClient(cfg, deps)
 	require.NoError(t, err)
+	defer c.Shutdown()
 
 	limiter := c.rpcLimiter.Load().(*rate.Limiter)
 	require.Equal(t, rate.Limit(500), limiter.Limit())
@@ -869,7 +870,6 @@ func TestClient_ShortReconnectTimeout(t *testing.T) {
 		func() bool {
 			return len(cluster.Servers[0].LANMembersInAgentPartition()) == 2 &&
 				len(cluster.Clients[0].LANMembersInAgentPartition()) == 2
-
 		},
 		time.Second,
 		50*time.Millisecond,
@@ -901,6 +901,7 @@ func TestClient_RPC_Timeout(t *testing.T) {
 		c.MaxQueryTime = 200 * time.Millisecond
 		c.RPCHoldTimeout = 50 * time.Millisecond
 	})
+	defer c1.Shutdown()
 	joinLAN(t, c1, s1)
 
 	retry.Run(t, func(r *retry.R) {