itest+lntest: migrate lntemp to lntest

This commit performs the takeover that `lntemp` is now promoted to be
`lntest`, and the scaffolding is now removed as all the refactoring is
finished!

lntest/rpc/peers.go

@@ -0,0 +1,39 @@
+package rpc
+
+import (
+	"context"
+
+	"github.com/lightningnetwork/lnd/lnrpc/peersrpc"
+	"github.com/stretchr/testify/require"
+)
+
+// =====================
+// PeerClient related RPCs.
+// =====================
+
+type (
+	AnnReq  *peersrpc.NodeAnnouncementUpdateRequest
+	AnnResp *peersrpc.NodeAnnouncementUpdateResponse
+)
+
+// UpdateNodeAnnouncement makes an UpdateNodeAnnouncement RPC call the peersrpc
+// client and asserts.
+func (h *HarnessRPC) UpdateNodeAnnouncement(req AnnReq) AnnResp {
+	ctxt, cancel := context.WithTimeout(h.runCtx, DefaultTimeout)
+	defer cancel()
+
+	resp, err := h.Peer.UpdateNodeAnnouncement(ctxt, req)
+	h.NoError(err, "UpdateNodeAnnouncement")
+
+	return resp
+}
+
+// UpdateNodeAnnouncementErr makes an UpdateNodeAnnouncement RPC call the
+// peersrpc client and asserts an error is returned.
+func (h *HarnessRPC) UpdateNodeAnnouncementErr(req AnnReq) {
+	ctxt, cancel := context.WithTimeout(h.runCtx, DefaultTimeout)
+	defer cancel()
+
+	_, err := h.Peer.UpdateNodeAnnouncement(ctxt, req)
+	require.Error(h, err, "expect an error from update announcement")
+}