Repo got renamed

[marcoscaceres]

PSA: repo was renamed to adhere to the WICG naming policy as part of WICG/admin#112

[foolip]

Links in the spec itself will need to be updated to https://wicg.github.io/web-otp/. Adding that to the repo settings so it shows up at the top right on https://github.com/WICG/web-otp would be good too.

[marcoscaceres]

Set up redirect and updated the front page of the repo to point to https://github.com/WICG/web-otp