Locking status is not checked on updating diagrams using API

[Geert Bellekens]

Details:
Using the API I can update diagrams and DiagramObjects for diagrams that are read-only in the GUI.
- Diagrams not locked when using "Require User Lock to Edit"
- Diagrams not checked out when using version control


Steps to Reproduce:
Write a script that updates Diagram properties, or DiagramObject properties
Execute this script on a diagram that is either
- not locked when using "Require User Lock to Edit"
- not checked out when using version control
Notice that you don't get an error, and EA happily updates the supposedly read-only diagram.
This is in contrast to other API objects, such as EA.Element that do honor the read-only status.

Reported

Geert