itest: add itest covering the leader healthcheck

itest/lnd_no_etcd_dummy_failover_test.go

@@ -8,3 +8,7 @@ import "github.com/lightningnetwork/lnd/lntest"
 // testEtcdFailover is an empty itest when LND is not compiled with etcd
 // support.
 func testEtcdFailover(ht *lntest.HarnessTest) {}
+
+// testLeaderHealthCheck is an empty itest when LND is not compiled with etcd
+// support.
+func testLeaderHealthCheck(ht *lntest.HarnessTest) {}