Update langs.json to add Punjabi language

[satnamsvirdi]

Hi React team,

I want to help with translating React documentation into my native language, Punjabi (also spelled as Panjabi).

I have previously worked on translating WordPress and Vivaldi Browser into Punjabi. As a React developer, I aim to ensure the accuracy of the translation to match the English version.

At this time, I do not have any other maintainer to join me on this project, but I am willing to search for someone who would be interested in joining if they agree to be a part of it.

Best, Satnam S Virdi