Models docs doesn't contain mentioned column tags table

[The user guide](https://tathougies.github.io/beam/user-guide/models/#column-tags) and [models.md#L117-L122](https://github.com/tathougies/beam/blame/b616812d992a6f05f7827659a5e0824235bb3e8c/docs/user-guide/models.md#L117-L122) mention a table of column tags and their meanings, but there isn't one.
