ambiguous definition of `isValid()`

**Describe the bug**
A clear and concise description of what the bug is.
### dayjs

### moment

**Expected behavior**
A clear and concise description of what you expected to happen.

```ts
dayjs('2022-04-32').isValid() // false
```

or **is there any difference of `isValid()` between moment and dayjs**

**Information**
- Day.js Version 1.11.0
- OS: macOS
- Browser 100.0.4896.75
- Time zone: GMT+0800 (中国标准时间)