`tz()` produces incorrect time when passing in milliseconds since the epoch near DST boundary.

**Describe the bug**

```ts
const dayjs = require('dayjs');
dayjs.extend(require('dayjs/plugin/utc'));
dayjs.extend(require('dayjs/plugin/timezone'));

// On March 13, 2022 in America/Montreal, at 2:00am, we roll the time back by 1 hour.
// This is the exact millisecond when that happens:
const dstBoundary = 1647154800000;

// This should obviously be true, and it is.
console.log(dayjs.tz(dstBoundary - 1, 'America/Montreal').valueOf() === dstBoundary - 1);

// This should also obviously be true, but it is false. :(
console.log(dayjs.tz(dstBoundary, 'America/Montreal').valueOf() === dstBoundary);
```

**Expected behavior**

When explicitly setting the time as a value in ms since the epoch, dayjs should not change the time we set, but here it does, rewinding time by one hour. `1647154800000` and `1647151200000` are two very different times.

**Information**
- Day.js Version: v1.10.8
- OS: MacOS
- Browser: node v16.14.0
- Time zone: America/Montreal