dayjs.utc(dayjs(), 'YYYY') is Invalid Date

**Describe the bug**
console.log(dayjs.utc(dayjs(), 'YYYY'));

result

```
M
$D: NaN
$H: NaN
$L: "en"
$M: NaN
$W: NaN
$d: Invalid Date {}
$isDayjsObject: true
$m: NaN
$ms: NaN
$s: NaN
$u: true
$x: {}
$y: NaN

```

dayjs@1.11.10

Start by running the reported dayjs.utc(dayjs(), 'YYYY') example against dayjs 1.11.10 and inspect the UTC and parsing entry points involved in that call. Trace how the existing date object and format argument are handled, then add a regression test defining the expected result before confirming the call no longer produces Invalid Date.

Written by the indexing model from the issue text.