weekOfYear shows wrong calender week at the turn of the year when using the "pt" locale

[MarinaFernandes]

Describe the bug
The 2020-12-31 should be calender week 53 but it shows as calender week 1.
(similar issue: #1264)

Expected behavior
https://runkit.com/marferna/6006c2f0e5d69000136b7ad0
We expected the example to output:
"With this date we are in week number: 53" and not 1;
"The current week is: 3" and not 4.

Information

• Day.js Version 1.10.3
• Browser Chrome 87.0.4280.141

[iamkun]

would you like to submit a PR to fix this? all we have to do is to add a 'yearStart: 4' to https://github.com/iamkun/dayjs/blob/dev/src/locale/pt.js

to indicate that

The week that contains Jan 4th is the first week of the year.

the same as https://github.com/iamkun/dayjs/blob/dev/src/locale/zh-cn.js

[MarinaFernandes]

All right @iamkun,
I will submit the PR.
Thank you for the quick answer!

[iamkun]

fixed