tapBar prop missing in bottom-tabs component props

I'm currently working on a project that requires a top bar to be added to the bottom-navigation.

An example is the *topBar* in [material-top-tab-navigator](https://reactnavigation.org/docs/material-top-tab-navigator#tabbar).

I'm using material-bottom-tab-navigator which is a wrapper around react-native-paper

Please, this is important and I'll need it to continue my project.

从 material-bottom-tab-navigator 组件开始，将其可用的 props 与 issue 中链接的 material-top-tab-navigator 文档进行比较。确定应如何暴露所请求的 topBar prop，并验证 bottom-navigation 组件是否支持所请求的行为。

由索引模型根据 Issue 内容生成。