Add bundling-modeler example

[barmac]

Proposed Changes

This adds an example for bundling modeler. This is also the only setup in which I was able to reproduce bpmn-io/dmn-js#889

Checklist

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• Brief textual description of the changes present
• Visual demo attached
• Steps to try out present, i.e. using the @bpmn-io/sr tool
• Related issue linked via Closes {LINK_TO_ISSUE} or Related to {LINK_TO_ISSUE}