Camunda-modeler: Unknown attribute camunda:calledElementVersionTag

[tasso94]

__Describe the Bug__
The following warning can be seen in the log:
```
Imported BPMN diagram with 1 warning [warning]

unknown attribute [warning]
```

__Steps to Reproduce__

1. Create a Call Activity in a BPMN file
2. In Properties Panel...
   
   
   
   1. Select BPMN as call activity type
   
   
   2. Specify any value for Called Element Input
   
   
   3. Select versionTag as Binding
   
   
   4. Specify any value for Version Tag
   
   
3. Save the BPMN file and close it
4. Open the BPMN file again
5. Open the Log

__Expected Behavior__

The warning is not shown.

__Environment__
Camunda Modeler Version: 2.2.3 (2.2.3.2044)

[nikku]

Seems like the extension is not implemented in camunda-bpmn-moddle.

[nikku]

Needs fix via https://github.com/camunda/camunda-bpmn-moddle/issues/43.

[nikku]

Closed via https://github.com/camunda/camunda-modeler/commit/1cd510d548b5004ed6116193b4b220759f334f8c.

[nikku]

Thanks @pinussilvestrus!

[nikku]

Released via Camunda Modeler v2.2.4.