otm_schema.json missing `package` property in `representationElement`

[xntrik]

This is referenced in https://github.com/iriusrisk/OpenThreatModel/blob/main/EXAMPLE.json#L177

[dantolin-iriusrisk]

Hi, @xntrik! Thank you for the warning! Yes, let us add this property to the standard docs and schema. Although it is already in the example, we want to be careful and upgrade the version of the standard to better align with the tools using it so that we will make this change in an internal task. I will update this issue as soon as the change is delivered.

[xntrik]

Sounds good. I've linked a PR too