multi: warn user if they try to switch db types

Warn a user if they attempt to initialise a new db type (sqlite or
postgres) if an old bbolt db file is found.

config_builder.go

@@ -830,7 +830,7 @@ func (d *DefaultDatabaseBuilder) BuildDatabase(
 			cfg.Watchtower.TowerDir,
 			cfg.registeredChains.PrimaryChain().String(),
 			lncfg.NormalizeNetwork(cfg.ActiveNetParams.Name),
-		), cfg.WtClient.Active, cfg.Watchtower.Active,
+		), cfg.WtClient.Active, cfg.Watchtower.Active, d.logger,
 	)
 	if err != nil {
 		return nil, nil, fmt.Errorf("unable to obtain database "+