[Feature Request] el-tabs components do not integrate well with el-badge components

### Existing Component
是

### Component Name
el-tabs; el-badge

### Description
in case of the componet el-tabs used the css overflow:hidden ,now the component el-tabs can not get along with the comonent el-badge as the picture I provide ,
由于el-tabs组件使用了overflow:hidden的样式,导致没法在tab上添加el-badge, 超出隐藏了
,
如上图,如果要弄成这样的, 目前的el-tabs不能很好的实现