refactor: use a more straightforward return value

Signed-off-by: fuyangpengqi <995764973@qq.com>

lnrpc/invoicesrpc/addinvoice_test.go

@@ -89,7 +89,7 @@ func (h *hopHintsConfigMock) FetchChannelEdgesByID(chanID uint64) (
 	policy2, ok := args.Get(2).(*models.ChannelEdgePolicy)
 	require.True(h.t, ok)
 
-	return edgeInfo, policy1, policy2, err
+	return edgeInfo, policy1, policy2, nil
 }
 
 // getTestPubKey returns a valid parsed pub key to be used in our tests.

lnrpc/routerrpc/router_server_deprecated.go

@@ -118,7 +118,7 @@ func (s *Server) SendToRoute(ctx context.Context,
 		Failure:  resp.Failure,
 	}
 
-	return legacyResp, err
+	return legacyResp, nil
 }
 
 // QueryProbability returns the current success probability estimate for a