The links to RFC3339 stopped working

[sbaechler]

The target of the RFC3339 link on the page https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#data-types does not exist anymore.

There is only a 404 page.

RFC3339 is available under https://www.rfc-editor.org/rfc/rfc3339

[handrews]

This was fixed in January- thanks!