use Fx to start and stop the host, swarm, autorelay and quicreuse (#2118)

* config: refactor AutoNAT construction into separate method

* config: use a lifecycle hook to start listening on swarm addresses

* use Fx to construct the host

* add a test for constructing a routed host

* use Fx hooks to start the host

* config: use Fx lifecycle hooks to start AutoRelay and for PeerRouting

* basichost: don't close the swarm

The swarm is not constructed by the basic host, thus is shouldn't be
closed by it.

* config: use Fx hook to close the quicreuse connection manager

* test for goroutine leaks when starting/stopping fx

To do this, I've had to move a few leaky tests into a separate package.
I've filed a bug for the AutoNAT issue (#2743) but the "error on
startup" issue is going to require some pretty invasive changes (we need
to construct _then_ start).

* go fmt

* Ignore one more top function

* Typo

* Ignore any not top

---------

Co-authored-by: Sukun <sukunrt@gmail.com>
Co-authored-by: Steven Allen <steven@stebalien.com>
Co-authored-by: Marco Munizaga <git@marcopolo.io>

leaky_tests/README.md

@@ -0,0 +1 @@
+Tests that leak goroutines for various reasons. Mostly because libp2p node shutdown logic doesn't run if we fail to construct the node.

leaky_tests/leaky_test.go

@@ -0,0 +1,26 @@
+package leaky_test
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/libp2p/go-libp2p"
+	"github.com/stretchr/testify/require"
+)
+
+func TestBadTransportConstructor(t *testing.T) {
+	h, err := libp2p.New(libp2p.Transport(func() {}))
+	if err == nil {
+		h.Close()
+		t.Fatal("expected an error")
+	}
+	if !strings.Contains(err.Error(), "_test.go") {
+		t.Error("expected error to contain debugging info")
+	}
+}
+
+func TestAutoNATService(t *testing.T) {
+	h, err := libp2p.New(libp2p.EnableNATService())
+	require.NoError(t, err)
+	h.Close()
+}