[Bug Report] el-autocomplete emits `blur` when selecting from the dropdown

### Element UI version
2.12.0

### OS/Browsers version
Ubuntu 18.04.5 / Google Chrome 85.0.4183.83

### Vue version
2.6.10

### Reproduction Link
https://jsfiddle.net/b4wz7fqn/5/

### Steps to reproduce
Click the ``. Select one of the suggestions.

### What is Expected?
I expected the callback for `@select` to be called. And maybe `@blur` afterwards... But only AFTER `@select`, otherwise there is no way to know whether the user is clicking out or not.

### What is actually happening?
The callback for `@blur` is called, which means that I cannot know if the user is clicking out or just selecting something from the dropdown.