Enable default no-else-return rule

What does this MR do and why?

Enable no-else-return rule by removing it's override allowElseIf, this rule seems to have been disabled for historical reasons, during a migration of airbnb-base 12.1.0 -> 13.1.0 5 years ago. So I see no reason to keep it.

  no-else-return:
    - error
    - allowElseIf: true

We can use --fix to safely fix it automatically, so I see no reason to not update it.

Screenshots or screen recordings

NA

How to set up and validate locally

Changes in this MR were not manual, after removing the no-else-return I simply ran:

```sh
yarn eslint --ext .js,.vue . --fix
yarn run prettier --write '**/*.{js,vue}'
```

MR acceptance checklist

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