customParseFormat plugin set random values when parsing invalid date

Hello,

When trying to parse some invalid date like `"54/42/0000 00:00", "MM/DD/YYYY HH:mm"`, dayjs doesn't set the date as invalid and set a "random" value instead.

You can test here with a comparaison with moment [https://codesandbox.io/s/eager-frost-x1ng0](https://codesandbox.io/s/eager-frost-x1ng0).

```js
import moment from "moment";
import dayjs from "dayjs";
import customParseFormat from "dayjs/plugin/customParseFormat";

dayjs.extend(customParseFormat);

const momentDate = moment("00/00/0000 00:00", "MM/DD/YYYY HH:mm");
const dayjsDate = dayjs("00/00/0000 00:00", "MM/DD/YYYY HH:mm");

console.log("moment", momentDate, momentDate.isValid());
console.log("dayjs", dayjsDate, dayjsDate.isValid());

const otherMomentDate = moment("54/42/0000 00:00", "MM/DD/YYYY HH:mm");
const otherDayjsDate = dayjs("54/42/0000 00:00", "MM/DD/YYYY HH:mm");

console.log("other moment", otherMomentDate, otherMomentDate.isValid());
console.log("other dayjs", otherDayjsDate, otherDayjsDate.isValid());
```

Thank you :)