presto-main/src/main/java/io/prestosql/metadata/CatalogManager.java/CatalogManager/removeCatalog
class CatalogManager:    public Optional<CatalogName> removeCatalog(String catalogName)
    {
        return Optional.ofNullable(catalogs.remove(catalogName))
                .map(Catalog::getConnectorCatalogName);
    }