[Bug Report] selection Disorder

### Element UI version
2.13.2

### OS/Browsers version
Chrom

### Vue version
2.6.12

### Reproduction Link
https://jsfiddle.net/mmx38qxw/#no_link_ignore

### Steps to reproduce
the order of selection is to append after selection, resulting in the different order of the selected and view

codePath:\node_modules\element-ui\packages\table\src\util

methodName:toggleRowStatus

### What is Expected?
same order as view

### What is actually happening?
not in the same order as the view