umd 分组件引用，出现Failed to mount component: template or render function not defined。望哪位大佬告知原因

根据官方umd构建https://doc.vux.li/zh-CN/install/umd.html。官方本身demo，umd_component_include_single.html也报组件渲染错误。

Start with the UMD installation documentation and the referenced demo file, umd_component_include_single.html. Reproduce the reported “Failed to mount component: template or render function not defined” error using the official demo, then trace the component inclusion and rendering setup. Done means identifying the cause and documenting or fixing the behavior in the demo and its related documentation.

Scritto dal modello di indicizzazione a partire dal testo della issue.